Pulaski, VA

 
Population: 34 k
Solar Delay in minutes: 23
With DST, Delay in minutes: 83

#1 Permanent Standard Time

 
% Sunrises after 7:00 AM: 28%
Latest Sunrise: 7:35

#2 Memorial Day DST

 
% Sunrises after 7:00 AM: 28%
Latest Sunrise: 7:35

#3 1966-2006 DST

 
% Sunrises after 7:00 AM: 42%
Latest Sunrise: 7:45

#4 2007 Current DST

 
% Sunrises after 7:00 AM: 51%
Latest Sunrise: 7:50

#5 Permanent DST

 
% Sunrises after 7:00 AM: 58%
Latest Sunrise: 8:35
In the above map, we see three appropriate time-zone boundary lines. The red areas to the left of these black boundary lines show inappropriate time zone areas that now exist. In contrast, under normal conditions these areas would have had light map colors and few dark mornings. Try moving your cursor up and down where a long DST in the Midwest produces 61% dark mornings. Doing so from north to south, and vice versa, illustrates how dark mornings correspond to map color. Along the same path, a short DST would have been close to a safe 36% (option #1 or #2). Points west of the 37% DM Threshold tend to increase chronic disease. Percentage of days with sunrises after 7:00 AM are shown in this map table. The higher the percentage of darkness, the more adverse the yearly impact, and conversely the lower the percentage of dark mornings the more beneficial the influence. Each map color approximately represents a range of similar percentages. At the cursor, when the map says, "Short DST," it often could have just as readily said, "Permanent Standard Time." Permanent Standard Time, option #1, and a summertime-only DST, option #2, are often about the same. Especially with corrected time zones, they are almost identical. The dark red map regions disrupt circadian influence, they are economically harmful, and they cause discomfort for those of us who are needlessly compelled to get out of bed one to two hours earlier on cold, dark winter mornings. "More than 50% of all gene expression is under circadian control," as Michael Rosbash pointed out in his Nobel Prize in Physiology or Medicine Lecture. In the early morning, circadian clocks are reset in response to the sun’s light-dark cycle. Circadian hormones widely influence how our bodies function.
Nobel Prize Circadian Image
Long seasons of early morning darkness impair cognitive function in school. In many regions, they endanger children waiting for school buses in pitch black darkness. As Google's AI puts it, "More than half of all fatal accidents involving school-aged pedestrians occur in the dark, making the morning rush during DST a particularly hazardous time." Adverse economic and chronic-disease impact of a large positive delay is often described as the "Western Edge Effect." To the question, "What is the impact of 'The Western Edge' effect?," Google's AI Overview responded, in part:

The "Western Edge" effect describes how living in the western part of a time zone, where sunrise and sunset are later relative to clock time, leads to worse health outcomes, especially with Daylight Saving Time (DST), causing more sleep loss, higher risks of diabetes, heart disease, obesity, and certain cancers, plus lower income, due to disruption of our natural circadian rhythms and misalignment with the sun's schedule. People on the western edge get less sleep because mornings start later by the clock, forcing them to wake in darkness, disrupting their internal clocks more severely than those on the eastern edge.

Key Impacts of the Western Edge Effect:

  • Health Risks: Higher rates of obesity, diabetes, heart disease, and breast cancer.
  • Sleep Deprivation: People get less sleep due to later sunrises, leading to daytime fatigue and poorer cognitive function.
  • Economic Costs: Lower per capita income and significant economic losses from reduced productivity and absenteeism.
  • Accident Rates: Increased risks of accidents, including fatal car accidents, due to impaired alertness and reaction times.
  • Mental Health: Links to higher rates of depression and suicide, as circadian misalignment disrupts mood regulation.

…

The DST Connection:

The effect is exacerbated by Daylight Saving Time because it shifts the sun an hour later, making these western-edge problems (late sunrises/sets) even more pronounced for those living on the western side of a time zone. Standard time, conversely, is better aligned with natural light, providing a more consistent schedule and reducing these risks.

Starting at the Atlantic Ocean and moving your cursor over the map from east to west, you can simulate the changes in morning darkness that fuel the Western Edge Effect. In the Northeast, the difference between the Western Edge and the Atlantic is huge. The greater the percentage of days with dark mornings, the more adverse the effect. Under natural conditions, 37% DM would have been the max. In the dark red map areas during DST, sunrises are delayed 92 to 118 minutes, effectively delayed one and a half to two hours later than under natural conditions. Because of corrupted time zones, the map is filled with 29% too many inappropriate, high-delay counties and, at the same locations, contains too few low-delay counties. Folks who wear fitness devices and attend to their health in other ways often do so because they want optimum health. In the face of high delays and many dark mornings, will they get it? To the point, should those in the dark red regions in the above map reasonably expect to be at the top of their game??
 

The Unfolding of Spring

The Question: "From roughly Jan 27 until April 20, natural morning sunlight increases at the rate of slightly more than one minute a day. On March 8, DST takes away 60 minutes of that morning sunlight. How does this influence human perception of the seasonal unfolding of Spring?"
Morning sunlight as Spring Unfolds
The Response: This is an excellent question, because it gets at something people feel but rarely articulate: DST disrupts our sensory and biological experience of spring itself. Here’s how the March clock change alters human perception of the season.

1. Spring normally unfolds as a smooth, daily gain of morning light [shown in the graph]

From late January through mid-April, morning sunrise advances at a remarkably steady pace—just over one minute earlier each day. That slow, reliable change is one of nature’s strongest seasonal signals. Humans evolved to register this in multiple ways:
  • Earlier light reaching the eyes shortly after waking
  • Gradual improvement in morning alertness
  • A felt sense that “days are opening up”
  • Emotional cues tied to renewal and momentum
This is not abstract. Morning light is the primary anchor for circadian timing and seasonal mood.

2. DST abruptly erases ~60 days of progress overnight

When DST begins in early March, the clock jumps forward one hour. Biologically and perceptually, that means: The morning light of late January suddenly returns. Instead of experiencing the accumulated gains of early spring, people wake up to:
  • Darkness again
  • Cold-feeling mornings
  • Heavier grogginess
  • A sense that spring has “stalled” or gone backward
This is not subtle. It’s a cliff, not a slope.

3. The mind interprets this as seasonal disruption, not just sleep loss

People often describe early March after the shift as:
  • “Spring doesn’t feel real yet”
  • “It still feels like winter mornings”
  • “The days aren’t improving like they should”
That perception is accurate. DST disconnects clock time from the natural seasonal arc, so the body keeps waiting for a signal that is being withheld. Instead of spring arriving by accumulation, it is forced to arrive by decree.

4. Emotional and motivational effects follow the light, not the calendar

Morning light affects:
  • Mood regulation
  • Energy
  • Motivation
  • Seasonal affective symptoms
By removing an hour of the most biologically potent light at exactly the moment [shown in graph] when days are improving fastest, DST:
  • Blunts the psychological lift of early spring
  • Prolongs winter-like lethargy
  • Delays the sense of renewal people expect in March
This helps explain why DST is often experienced not as a “spring forward,” but as a spring interruption.

5. Western time zones feel this most strongly

On the western edge of time zones:
  • Sunrise is already late by the clock
  • DST pushes usable morning light even later
  • The seasonal setback is amplified
For many people in these regions, spring mornings do not truly arrive until April, even though the calendar insists it’s March.

6. Evening light cannot replace the lost signal

Evening daylight may look pleasant, but it does not provide the same seasonal information as morning light. Morning light:
  • Advances circadian timing
  • Signals seasonal progression
  • Improves morning alertness
Evening light:
  • Delays sleep
  • Blurs seasonal cues
  • Extends fatigue
So DST swaps the signal that tells us spring is arriving for one that tells the body to stay in winter mode longer.
Bottom line DST doesn’t just steal an hour of sleep — it steals the felt continuity of spring itself. By wiping out roughly two months of gradually accumulating morning light overnight, the clock change fractures our perception of seasonal unfolding. Spring still arrives astronomically, but our bodies are forced to wait, confused by a clock that insists time has moved forward while light says otherwise. In that sense, DST doesn’t usher in spring — it postpones our ability to feel it.

[Word for word, the above is ChatGPT's response to the question. Separately, the graph is derived from NOAA spreadsheet. In the spring, without DST, there is a substantially linear reduction in seasonal mortality from January 28 to June 14 (138 days). More on Human Seasonal Mood here.]

Worth noting: As seen in the above graph, a May 20 summertime-only DST would have minor influence, because only 5% of additional natural spring season sunlight is produced after May 20. On the other hand, a March 8 DST is enormously disruptive because 66% of spring sunlight is naturally produced after March 8. It is ironic and disorienting that at the precise instant when natural morning sunlight is giving us its fastest rate of increase in light, the March DST hits the dimmer switch. Seemingly, no good deed goes unpunished, even if it is provided by nature.
 

Background

DST Hurts. Bad time zones make it worse.
Way back in the day, each village had its own time. It was widely known that longitude and time marched in lockstep, 4 minutes for each degree of longitude. So, by sundials, solar noons, and calculations, local time was adequately kept in each village. The change came in 1883. Railroad schedules needed a time that covered large regions, not just separate times for each village. In this fashion, time zones were created to replace calculating time based on the sun's position at each location. Looking at 1883, 1899, 1913, and 1919–2024 time-zone maps, we find, however, that time-zone boundaries were not created or preserved as a reliable time-keeping standard. Particularly, Eastern Time boundaries sporadically moved westward. As Google's AI shows, "Each 15 degrees of longitude corresponds to one hour of time difference. This relationship forms the basis for time zones, where each zone typically spans 15 degrees of longitude." Fully nine hundred counties do not comply with this precept, and the noncompliance is often extreme. For example, Ontonagon County, Michigan lies deep in what should logically be Central Time, but remains on Eastern Time. When DST is in effect, local clocks effectively run two hours ahead of solar time. Severe time-zone misalignments of this kind create large circadian and health-related burdens. The five DST options shown next to each of the interactive maps are effectively active for 0%, 1/3, 1/2, 2/3, or 100% of the year, with a tendency to increase over time. The flipside of an extra hour of DST evening summer sunlight is that long DSTs increase morning darkness in the winter half of the year. Confined to 1/3 of the year, a summertime-only DST does not. This discussion deals with two arms of the problem: long DSTs and improper time zones. The combined DST-TZ adverse impact comes hand in hand with a high annual percentage of dark winter mornings and heavily delayed sunrises — both of which impact circadian function and harm health and the economy. The stated objective in the current Senate bill is: "To make daylight saving time permanent … " This objective is quite different from Permanent Standard Time, which also eliminates clock changes. Permanent Standard Time has the distinct advantage of being the most healthy of all alternatives. In complete contrast, Permanent DST stands out as being decidedly the most harmful. If you have any doubts, please consider past history and current reasons. Within its borders, any state can reject DST without congressional action (15 U.S. Code § 260a). If this provision is preserved, it may provide an alternative to permanent daylight saving time. The current DST beginning in March is active for two-thirds of the year. A true summertime-only DST is active for one-third of a year — half as long. DST and time zones are a story of excess. Had DSTs been short, had time zones been confined to the customary 15 degrees of longitude, neither would have caused harm. As it stands, they both do. Many economic arguments used to promote Daylight Saving Time have been shown by research to be dubious or outright false. Similar to other groups claiming economic DST benefits, the golf industry often asserts that from green fees and equipment sales, they derive $200 million to $400 million revenue annually from DST. Even if such figures happened to be accurate, on the other side of the ledger, they are dwarfed by the scale of health-harm costs that DST creates. It is estimated here that, by eliminating DST, five chronic diseases alone would reduce chronic disease expenses by roughly $45.8 billion. By scale, the $200 and $400 million golf estimates, are trivial (only 0.44% and 0.87% respectively of $45.8-billion healthcare costs created by DST-TZ). Elsewhere, if we look at the direct golf publicized impact of nearly $102 billion in 2022, it is comparatively small relative to only a single chronic disease: diabetes at $413 billion, its Group B alone being at $235 billion. Chronic disease harms together dwarf proposed dollar amounts of claimed DST economic benefits.
According to your preference, the DST-TZ fix, which we will often refer to, can employ either Permanent Standard Time or a short DST (such as a Memorial to Labor Day DST). Both have similar influence.

The program that we wrote to create the data for the three interactive maps, operates in this manner: For each of the 3,000 US counties, for each of the 365 days in a year, using NOAA methods it computes and then for each county stores the number of number of days in a year with sunrises after 7:00 AM. It does this for each of the five options, based on starting and ending dates: #1 Permanent Standard Time, #2 Memorial Day DST, #3 1966-2006 DST, #4 2007 Current DST, and #5 Permanent DST and for delay based on longitude and time zone. With this, roughly 5.5 million pieces of information support the maps [5,478,000=3000*365*5+3000].

To supplement this discussion, the excel DM spreadsheet v2.0 here provides, at a FIPS specific level, exact delays and trendline percentages of dark mornings for all counties in the continental United States. This is the only database of this kind that we are aware of. It may be useful for simulations and for exploring dark morning relationships in other national databases.

Egregious Time Zones

Eastern and Central Time zones have massively shifted westward since they were initially drawn in 1883 — about 378 miles from an appropriate point. A time-zone fix is imperative. Yet, as the Bureau of Transportation Statistics reports, in the past 20 years, only 15 counties have changed. These 378 miles are not pulled from thin air. At the median latitude for US counties (38.3°), each minute of delay in a time zone translates to 13.5 miles. At a 58-minute delay, the time zone is 28 minutes longer than the appropriate 30-minute maximum. Thus, the 378 miles [= 28*13.5]. An aside: At latitude 38.3°, a one-hour time zone spanning 15 degrees of longitude corresponds to 820 miles. Of the 900 inappropriate time-zone counties, fully half of these counties (yes, 450 counties) are currently more than 100 miles further westward than their time zone's appropriate upper limit. This graph and table, as well as the spreadsheet, show the details.
Time Zone Miles from appropriate point
PercentileMiles
1%350
2%300
5%250
13%200
27%150
Half
50%		100
75%50
88%25
These extreme distances, often greater than 50 miles, violate the appropriate 15-degrees-of-longitude basis for time zones. By themselves alone, improper time zones have fully doubled the extent to which the nation is desynchronized.

This doubling is from the unadulterated, normal 8.2 minute average solar delay to the current 16.9 minute average, as shown in DM spreadsheet v2.0. An aside. These sync values (8.2 and 16.9) carry additional significance because, as later will be seen, they approximate the difference between superior performance (8-delay and lower) and mediocre performance (17-delay). To the question, "In the continental United States, what are the economic and health effects of excessively broad time zones that span more than 15 degrees of longitude?" In part, Google AI Overview responded:

Broad time zones, especially living on the western edge where sunsets are late, disrupt circadian rhythms, causing sleep deprivation, obesity, diabetes, heart issues, and higher suicide rates, costing billions in healthcare; economically, this means lower productivity and wages, though late sunsets offer extra evening leisure time, balancing some effects. The misalignment of natural light with work/school schedules (social jet lag [desynchronization]) is the core problem, leading to significant public health burdens.

Health Effects

  • Sleep Disruption: Residents on the western edge sleep less (fewer than 6 hours) and wake more often, especially those with early work/school commitments.
  • Metabolic Issues: Higher rates of overweight (11%) and obesity (21%) are linked to late sunsets.
  • Cardiovascular Problems: Heart attack rates increase by 19% in these areas, notes New York Post.
  • Cancer & Suicide: Higher breast cancer risk and elevated suicide rates are observed, attributed to circadian disruption.
  • Mental Health: Chronic circadian disruption is linked to depression and mood disorders.

Economic Effects

  • Lower Productivity & Wages: Sleep deprivation reduces worker output, leading to about 3% lower wages on the late-sunset side, reports Hartford Courant.
  • Healthcare Costs: The associated health problems contribute to billions in annual healthcare costs, even with conservative estimates.

…

Repair Your Local Time Zone & See the Change

Now, move your cursor over this interactive map to consider a time-zone fix. The first column in the Table below is the same as in the first map. However, when a time zone is repaired, results appear separately in black in a second column. This second column shows a repaired time zone. It is empty when no time-zone change occurs. At your cursor, in each second column section, the top right percentage reveals the best option (Short—or no—DST and repaired time zone); lower left, the worst option (Current DST and current time zone). The repair produces four 15-degrees-of-longitude, pure one-hour time zones (EST, CST, MST, PST) with solar delays falling within a ±30 minute range. The black time-zone boundary lines are consistent with Coordinated Universal Time (UTC) time zones that we now use. Eastern time begins at longitude -67.5°; Central, at -82.5°; Mountain, at -97.5°; and Pacific, at -112.5°. Positioning time zones in this orderly fashion results in the highly favorable outcomes shown, when appropriate, at your cursor and in the second column of the map Table. Let your cursor travel along the three black boundary lines. While you will encounter some urban centers that require special consideration, it is surprising how many low population counties exist along these routes. Currently a dozen states are already split between two time zones: Florida, Michigan, Indiana, Kentucky, Tennessee, Nebraska, Kansas, Texas, North Dakota, South Dakota, Oregon, and Idaho. To eliminate high delays, 479 counties in the Eastern time zone, 370 in the Central, and 47 in the Mountain need to change. In this group of counties, when, instead of sticking with the current DST, we repair time zones and select either Permanent Standard Time or a Memorial to Labor Day DST, we go from an average 64% of sunrises after 7:00 AM to 4%. On average, our latest sunrise goes from 8:04 AM to 6:54 AM. By these DST-TZ changes, we reliably start our winter mornings with adequate sunlight. In 900 US counties, we did not and could not do this before, because we were locked into an inappropriate DST and inappropriate time zones.
 

Delay Measures Being Out of Sync, Particularly the 30 Minute Delay

Delayed sunrises reflect the influence of location. Any delay exceeding 30 minutes (roughly 58% dark mornings with the current DST) indicates a corrupted time zone. Overly dark winter mornings in the United States are entirely caused by unnatural time zones, primarily in the Midwest (and points directly south of it), and by excessively long DSTs. The interactive maps here show that we tend to wrongly attribute late sunrises in much of the northern half of the U.S. to northerly position when, in fact, the late sunrises are caused by inappropriate time zones and long DSTs.
County State DelayTime Zone Miles
From Appropriate
30 Minute Delay
1PresidioTX58372
2OntonagonMI57368
3DivideND54323
4CimarronOK50271
5VermillionIN50268
6MortonKS47232
7CanyonID47226
8MeadeKY45201
9HayesNE44192
10MelletteSD43176
11DadeGA42162
12HamiltonTN41144
13LibertyFL40129
14PrebleOH39116
15La PazAZ38106
16CherokeeNC3684
17BeaverUT3451
18BeaverheadMT3343
19OconeeSC3233
20City of NortonVA307

In the table here, we see the most westerly counties in each of the states having inappropriate time zones. Most of first ten of these are in northerly regions and are causing excessive morning darkness, not to mention causing an extra hour of blistering early morning cold throughout winter months. On the other hand, when symmetric time zones and a short DST are employed, even regions near the Canadian border have sufficient winter morning sunlight of the kind now evidenced in the states of Maine, New Hampshire, and Vermont. During the two-thirds of the year when the current daylight saving time is active, the extent of desynchronization is even greater than shown in the table. At the extreme it is 58+60=118 minutes, almost two hours. To our benefit, a fix combining symmetric time zones and a short DST (or Permanent Standard Time) can return us to approximately natural conditions. It can easily produce a winter season with a modest 2.3 months of sunrises later than 7:00 AM (only 19% of the year, 69 days), with no county exceeding 135 days (37% of the year, 4.4 months) of late sunrises. This median 2.3 months of reduced early morning sunlight is generally in line with expectations of what winter mornings should look like. Indeed, it is precisely what unadulterated median winter mornings do look like. In sharp contrast, the current DST and its time zones are now delivering two and a half times as many dark mornings! By a wide margin, we humans have made winter seasons far, far more unattractive than they need to have been. And that nastiness has had influence. [Delay at your location, specifically solar delay, is shown in the map tables and in DM spreadsheet V2.0.] Delay at the core: Normally time-zone time is good enough, but when a time zone is corrupted, mischief takes hold. In each county, minutes of delay measure the extent to which a location is out of sync with time. When we look at a clock or watch, we instinctively assume it shows true time. Not so. We instead are seeing "time-zone" time. Accurate, proper time (local solar time) is buried within the time zone. At each location, the average minutes to this point is measured by minutes of delay shown in the map tables. This offset has wide impact and varies according to your location. It defines the sun's local light-dark cycle and can be readily determined by formula. When within this discussion you look at graphs and tables, keep in mind that delay precisely indicates your location within a time zone. Considering delay from a different angle: Delay measures proximity to being in sync. In each time zone there is an instant (local solar noon) when the sun is directly overhead at your location, and morning and afternoon hours are effectively equally long (the midday). When clock time is also at 12 o'clock noon, the position of the sun and clocks are in sync, and solar delay, as referred to here, is zero. When, by your watch, it takes longer for the sun to arrive at this midpoint, the delay is positive. A negative delay indicates that the sun arrives before your watch time indicates. With DST or an improper time zone, delay is always positive. Only eleven states have negative delays when all their counties are averaged. The sun's delay and solar delay (often simply abbreviated as delay) all carry the same meaning. At all hours of the day, delay is present. This misalignment is transformative. When it exceeds a 30-delay or the DST is long, it creates overarching seasons of winter morning darkness that would not normally exist. In practice, locations seldom are in perfect sync. It is delay that by degree ultimately tells the out-of-sync story, which in essence is the story of the vast reaches of the Western Edge Effect. Just as the mantra — "Location, Location, Location" — is ubiquitous in real estate, so too location applies when considering delay and dark mornings. It is arguable which should be a gold standard, "delay" or "percentage of dark mornings." Take your pick. Delay indicates the extent to which a location is in sync with the sun's light-dark cycle. Percentage of dark mornings goes a step further to reflect the combined influence of delay and Daylight Saving Time at a given location.

Broken Time, Broken Health

Why “Social Jet Lag” Is the Wrong Name for a Very Real Problem

Modern medicine and popular science often describe our misaligned body clocks using the phrase “social jet lag.” It sounds clever. It sounds relatable. And unfortunately, it’s deeply misleading.

For most people, jet lag means one thing:
a short-term annoyance after flying across time zones—grogginess, bad sleep, maybe a headache—something that fades after a few days.

Even medical sources agree. Jet lag is typically described as a temporary inconvenience, not a serious or lasting condition.

So here’s the problem:
what we’re experiencing at home is not jet lag.

Jet Lag Ends. Time Manipulation Doesn’t.

Jet lag happens when you move across time zones.
The body adapts.
The discomfort resolves.

But what happens when time itself is moved, and you stay put?

That’s what inappropriate time zones and Daylight Saving Time do—especially for people living on the western edge of time zones, a phenomenon known as the Western Edge Effect. In these locations, the sun rises later by the clock, forcing millions of people to wake, work, eat, and sleep out of sync with natural light every single day.

This is not temporary.
This is not occasional.

This is chronic biological misalignment, tied directly to geography and policy.

Language Shapes Understanding — and “Social Jet Lag” Trivializes the Issue

Words matter, especially when discussing public health.
The phrase social jet lag unintentionally tells people:

  • “This is minor.”
  • “This is normal.”
  • “This will pass.”
  • “You just need to adapt.”

But chronic circadian misalignment does not pass.
It accumulates.
It affects sleep quality, metabolic health, mood, learning, productivity, and long-term disease risk.

By borrowing the language of a fleeting travel nuisance, the term shrinks a serious, population-wide issue into something dismissible.

It’s not just inaccurate—it actively undermines public understanding.

A Rhetorical Own-Goal

Using “social jet lag” in conversation is like arguing with a metaphor that shoots your case in the foot before you finish your sentence.

You’re trying to explain something persistent, structural, and imposed, while using a term that implies something temporary, optional, and self-inflicted.

One step forward.
Two steps back.

It’s a self-sabotaging choice of language.

Even Wikipedia Makes It Worse

To add to the confusion, Wikipedia redirects “social jet lag” to Delayed Sleep Phase Disorder (DSPD).

That’s not helpful—it’s disorienting.

DSPD is a clinical sleep disorder, affecting a subset of individuals.
Time-zone-induced circadian misalignment affects entire populations, regardless of diagnosis.

Conflating the two muddies the waters for casual readers and blurs the line between individual pathology and systemic time distortion.

Call It What It Is

We don’t need cute metaphors.
We need accurate language.

This issue is about delay, desynchronization, and chronic circadian misalignment caused by time policy. That misalignment damages health and the economy.

Whatever term we ultimately settle on, it should reflect three core truths:

  1. It’s chronic, not temporary
  2. It’s geographically imposed, not self-inflicted
  3. It affects millions, not travelers passing through

Until then, “social jet lag” remains a catchy phrase that obscures more than it explains—and stands in the way of serious public discussion about how badly we’ve broken time itself.

[The above is a ChatGPT rewrite of a first-draft, mini essay: Broken Time, Broken Health. Two decades ago, 2006, the term "social jet lag" first appeared in the literature.]

Map Side-by-Side Comparison, Before & After

In 15-degrees-of-longitude, symmetric one-hour time zones, delays are limited to a ±30 minute range. In practice, US time zones are now profoundly lopsided. They strongly favor the western edge. That is why they are prone to producing health and economic problems. The "After" shows that throughout the United States, up to the Canadian border, you can have ample winter early morning sunlight for appropriate circadian entrainment. As in the previous interactive map, when a time zone is repaired, results appear separately in black in a second column. This second column shows a repaired time zone. It is empty when no time-zone change occurs. At your cursor, the top right percentage reveals the best option (Short—or no—DST and repaired time zone); lower left, the worst option (Current DST and current time zone). The "After" map on the right shows the time zone fix, which is to say a return to the precept of pure one-hour, 15-degrees-of-longitude, time-zone baselines. When we also go a step further and employ either Permanent Standard Time or a Memorial to Labor Day DST, the five new bands of map colors respectively hover around 0%, 12%, 20%, 24%, and 29% of days with dark early mornings, typically peaking at 21%, 25%, 29%, 33%, and 37%. Even the new dark "After" map colors are a cure. With the DST-TZ fix, they show only modest winter morning darkness. The fix returns us to approximately natural time. US Personal Income and stellar academic performance and key health categories have flourished at these percentages of darkness.
 

DST and Inappropriate Time Zones (DST-TZ)
Increase Chronic Disease Incidence Rates

The population with Coronary Heart Disease (CHD) grows when the percentage of dark mornings increases. It seems to be commonly believed that, excluding twice a year clock changes, DST is a free ride. That is not so. Fourteen CDC chronic health conditions are especially sensitive to percentage of dark mornings.
Highly Sensitive Heart, CHD, Incidence Rates

From about 30% to 32% dark mornings [a 1.5 to a 3-delay], the percentage of the population with heart (CHD) problems is low at about 5.6%. That population steeply grows when dark mornings increase to roughly 43% [a 15.5-delay], where it substantially plateaus.
Highly Sensitive Heart, CHD, Incidence Rates

By comparison, with a high percentage of dark mornings, cases of excessive weight gain even more sharply grow. The explosion in obesity cases at 37% dark mornings illustrates potency at the Threshold.
Incidence Rate Transition at Threshold

Similar to the prior graphs, “Leisure Time Physical Activity” and “General Health,” had bursts of favorable performance prior to the 32% DM point [3-delay]. In contrast to these favorable performances, once past the 37% threshold, incidence rates in all categories discussed here stay high. “Leisure Time Physical Activity” deserves special attention. In complete contrast to the assertion that DST promotes physical activity, the data shows that when the threshold is crossed, physical inactivity surges. While DST promises “more evening sunshine and more physical activity,” sleep debt and fatigue created by DST undermines the very energy people need to enjoy additional evening sunlight. DST dark mornings thus lead to physical inactivity. It is wrong to say that DST promotes physical activity. The message seems to be that 32% and fewer dark mornings tend to deliver superior performance. Those lower than 37% are usually quite good. The rest appear to suffer by comparison. The degree of that suffering is illustrated in the following Dark Morning (DM) Chronic Disease Model.

Notes: The data you see in the graphs here is pure, unsmoothed, centered rolling average – each datapoint supported by 900 counties. By virtue of large group size, the graphs should be reliable. The nine hundred county group size is exactly the same as used in the reduced longevity section, where best performance occurred at a similar 33% to 35% dark morning range [4 to 6-delay].

The Dark Morning Chronic Disease Model

The Dark Morning (DM) Chronic Disease Model starts with this little, but potent, table. It shows the increase in incidence rates when going from Group A (beneath threshold level) to higher dark morning levels, first to Group B (the high-DM level), then to Group C (the very high Top Quarter level). The ratio between the two suggests extent of change, General Health and Leisure Time Physical Activity showing the greatest extent of change.

The table then shows the now-existing incidence rates in fourteen health categories, culminating with the number of people who tend to benefit from a return to the healthy below-threshold level — a level that can be used as a proxy for Permanent Standard Time. The uniform message in all fourteen categories is that each of the increases are adverse. In these groups, Permanent Standard Time consistently turned out best.

Operating beneath the 37% Dark Morning (DM) Threshold, Group A in the following table is close to unadulterated Permanent Standard Time. [They both peak at 37% dark mornings, as illustrated in a following graph.] Compared to Groups B & C, Group A has the lowest dark mornings and lowest disease rates, as shown here.

When percentages at your cursor in the maps exceed 37%, those locations (Groups B & C) tend to produce increased incidence rates in all fourteen categories.

In this table, the last two columns indicate estimated potential benefit derived from staying beneath the 37% Dark Morning Threshold.

Benefit That Can Be Achieved By Living Beneath the 37% Threshold
(which is to say, Permanent Standard Time)
CDC
Category		Beneath Threshold
to Above Threshold
(Group A to B Incidence
Rate Increase)		Beneath Threshold
to Top Quarter
(Group A to C Incidence
Rate Increase)		RatioLow-DM
Incidence Rate
(Group A)		High-DM
Incidence Rate
(Group B)		Top Quarter
Incidence Rate
(Group C)		Number of Cases
At Start		Number of Cases After
Low-DM Incidence Rates
Universally Applied		Per Person
Annual
Medical Cost		Number of People
Directly Benefiting		Percentage
Benefiting
1Obesity8.1%14.5%1.8 32.39%35.02%37.08%86,702,62982,980,724$2,0853,721,9004.30%
2Disability6.0%8.5%1.428.39%30.09%30.79%75,138,25072,716,224$11,5522,422,0003.20%
3Smoking10.0%17.5%1.713.75%15.13%16.15%37,168,64735,210,193$6,4571,958,5005.30%
4Depression5.8%10.7%1.921.88%23.15%24.23%57,847,01156,056,008$2,2011,791,0003.10%
5Leisure Time
Physical Activity		4.2%9.3%2.223.08%24.06%25.22%60,516,05859,116,402$3,1731,399,7002.30%
6Cognition6.3%8.6%1.414.03%14.91%15.23%37,191,43835,947,246$6,2381,244,2003.30%
7COPD13.1%22.7%1.75.78%6.54%7.09%15,884,96414,816,261$2,9591,068,7006.70%
8Mental Health4.0%6.3%1.616.99%17.67%18.06%44,482,65143,522,337$2,394960,3002.20%
9Mobility5.6%8.8%1.612.12%12.80%13.19%32,009,83231,054,417NA955,4003.00%
10Diabetes6.2%9.8%1.610.32%10.96%11.33%27,335,31426,423,697$15,109911,6003.30%
11General Health3.6%8.2%2.317.42%18.04%18.85%45,496,26544,619,343NA876,9001.90%
12Heart, CHD7.1%10.2%1.45.60%6.00%6.17%14,923,59314,356,388$10,206567,2003.80%
13Cancer5.0%5.3%1.16.55%6.88%6.90%17,241,91016,781,306$10,730460,6002.70%
14Stroke4.0%7.3%1.83.03%3.15%3.25%7,935,8517,762,147$10,206173,7002.20%
Median5.90%9.05%1.713.90%15.00%15.70%1,014,5003.20%

(Number_of_People_Directly_Benefiting = Number_of_Cases_At_Start - Number_of_Cases_After_Low-DM_Incidence_Rates_Universally_Applied)

[Spreadsheet notes: CDC Places 2024 database and heading notes.] At the 8.5-delay point we split the CDC Places database into two groups. Group A has 1,070 counties with fewer than 37% dark mornings. This group effectively represents natural conditions. Group B comprises 2,020 counties, having more than 37% dark mornings. The severing at the 8.5 delay and the large number of supporting data points make reliable comparisons possible. We are given a low-DM adult population of 114,359,692 (Group A); a high-DM population of 141,808,473 (Group B), together totaling 256,168,165. It is this Total that we multiply by "Low-DM Incidence Rates" to get "Number of Cases After Low-DM Incidence Rates Universally Applied." Subtracting this from "Number of Cases At Start" yields "Number of People Directly Benefiting." "Increase" relates to differences between incidence rates. CDC "Leisure Time Physical Activity" cases denote prevalence of no leisure-time physical activity among adults. Group C Top Quarter Dark Mornings, begins at 32-delay, 773 counties. Group C overlaps Group B. All Group C created by faulty time zones (delay greater than 30). Incidence rates here refer to the percentage of the adult population having a specific malady. Per_Person_Annual_Medical_Cost= Total_Published_Medical_Expenditure_ for_Chronic_Disease_Category/ Number of Cases_At_Start.
An aside: Based on Smoking, Depression, Cognition, Diabetes, Heart-CHD, Cancer and Stroke alone (culling Obesity, Disability, Leisure Time Activity, COPD, Mental Health, and Mobility to approximate independence), a first approximation, using a product series, minimally suggests 56%, 58%, and 60% of the adult population respectively in Groups A, B, and C would suffer from at least one of the fourteen categories. Consistent with this analysis, the CDC indicates that chronic disease affects 60% adults in the US [https://www.cdc.gov/pcd/issues/2023/23_0120.htm ] From this, it appears that more than half of the adult population have a direct stake in in the matter.

Across a wide swath of the nation, we already benefit from the light-dark cycle and its resulting circadian responses. To state it plainly, the 1,070 low-DM counties in Group A have Dark Mornings (DM) lower than the 37% Threshold. As such, the Threshold and below can approximately simulate Permanent Standard Time. At the median in the first column, we find Group A, low-DM incidence rates are about 5.9% lower than in Group B (the 2,020 high-DM counties).

High-DM county conditions (Group B) are abnormal and do not naturally exist. They are above the 37% DM Threshold and produce higher incidence rates in all fourteen categories. With this rare fourteen-category, multipronged impact, we practically have a disease unto itself, a chronic DST Disease.

Instead, as shown in the table, if we stay beneath the threshold and universally apply low-DM incidence rates throughout each category, the number of cases plummet and the number of People Directly Benefiting escalate.

With the DM Chronic Disease Model, the table delivers an estimated reduction of almost four million obesity cases and produces over a million more people engaging in leisure time physical activity. These improvements along with those in the other categories can greatly benefit us, at the median about a million people per category. In this small model, the number of People Directly Benefiting is not intended to be precise, but to be an approximation of magnitude, which for all fourteen categories sum to 18.5 million fewer chronic disease cases, a 3.3% average effect [3.3%= 18,511,720/ 559,874,413. This includes time zone repair.].

With this, we see that those of us living above the 37% Threshold are only operating at 97% of potential. In large part, this is the price we pay for DST-TZ — a degraded performance for those of us in Group B.

At the extreme peak, the very high, now-existing Top Quarter Incidence Rates, all with inappropriate time zones, are shown for comparison. As characteristic of a corrupted time zone, these Group C cases occur at 59% dark mornings and above [a 32-Delay or higher]. The Group A to C large incidence rate increases, 9.05% at the median, show the health burden on the top quarter, apparently due to very high DM. In all fourteen categories in Groups A through C, there is an unambiguous, unvarying observation: With increasingly high dark mornings and ever higher delays, come increased incidence rates, reaching an apex in Group C.

Google's AI analysis of the above data reads, word for word, as follows:
The assessment indicates a direct positive correlation between increasing dark mornings (DM) and the incidence rates of all 14 listed CDC categories across Groups A, B, and C. Step 1: Data Analysis and Group Definitions The provided data establishes that for all 14 CDC categories, the incidence rate increases consistently as the "Dark Morning" (DM) classification shifts from Group A (fewer than 37% DM) to Group B (more than 37% DM) to Group C (top 25% highest DM). The incidence rate in Group A is the lowest, followed by Group B, and then Group C has the highest rate for every single condition. Step 2: Assessment of Influence The consistent upward trend in incidence rates across all categories (Obesity, Disability, Smoking, Depression, etc.) as the percentage of dark mornings increases suggests that a higher frequency of dark mornings is associated with a negative influence on public health within these specific groups. This data implies that communities experiencing more dark mornings may also experience a greater burden of chronic health conditions and mental health issues. Answer: The assessment indicates a direct positive correlation between increasing dark mornings (DM) and the incidence rates of all 14 listed CDC categories across Groups A, B, and C. As the frequency of dark mornings increases from Group A to Group B and then to Group C, the associated incidence rates for all chronic health conditions and behavioral factors listed in the data consistently rise.

If, from the table, one were to use the technique "total savings= per person medical cost* number of People Directly Benefiting" and sum the results, the total reduction could be in the neighborhood of $96.2 billion.

For those of us living at locations above the 37% DM threshold, a failure to improve creates a large and harmful drag in important areas of our day-to-day lives. Improvement is directly traceable to appropriate time zones and DST elimination.

Dark Morning Percentiles Remarks: This graph at percentiles from 5% to 95% defines percentages of Dark Mornings in US counties. In this section, the practical purpose of the graph is to illustrate the difference between the orange Current-Distribution-Cropped-at-37% curve used as a proxy and true Pure-Permanent-Standard-Time. That difference is a median 10% favoring permanent standard time. Rather than adjusting for the difference, it is left as is. By the true permanent-standard-time curve being lower than the orange proxy curve, the case for permanent standard time and Group A is understated, giving slightly more conservative estimates than those that would tend to exist. The curves also suggest vast health differences between us depending on where we live and its resulting dark mornings. By a wide margin, the pure-permanent-standard-time curve (with corrected time zones) is the preferred position. [Source: DM spreadsheet v2.0]

Morning Sunlight and Causal Inference

Question: When precise sunlight measurements are a definite independent variable (x-axis), can this in any way be a special statistical case where it is easier to assess causality? Google's AI Overview Response: Yes, using precise, well-measured, and physically grounded independent variables (like sunlight on the x-axis) is a special case that significantly facilitates the assessment of causality. While correlation does not equal causation, having a precise, exogenous (externally determined) independent variable reduces the ambiguity of the direction of influence and strengthens causal inference. This scenario acts as a "natural experiment" or a strong quasi-experimental design because it often satisfies key conditions for establishing causation: Why This is a Special Case:
  1. Clear Directionality: In observational studies, it is often hard to tell if X causes Y or Y causes X. With sunlight, the direction is clear, removing "reverse causality."
  2. High-Variance Inputs: Natural variation in sunlight (latitude, season, clouds) provides a broad range of data points for analysis, which improves statistical power, allowing for better identification of the relationship.
  3. Natural "Instrument": Because sun exposure is often independent of human, localized factors, it behaves like an instrument, helping to isolate the causal mechanism from confounding variables.
Limitations: While it makes it easier, it does not automatically prove causality. You must still account for:

 

Increased Chronic Medical Cost … Billions, Billions … All From DST & Distorted Time Zones

Fully 90% of US annual healthcare expenditures are for chronic disease and mental health conditions. DST-TZ is chronic, so too are the diseases it abets. If our objective, from a circadian-related public health perspective, were to curtail chronic disease, we would eliminate DST-TZ (& the Group B resulting from it). Increasing percentages of dark mornings resulting from DST and inappropriate time zones cause chronic disease increases in fourteen categories. Building on the Dark Morning Chronic Disease Model, we see in the following graphs that Group B (those above the threshold) have far, far greater chronic disease expenditures than Group A (beneath the threshold and similar to permanent standard time), which—especially at the low end—appear to protect against chronic disease.

Diabetes Cost Smoking Cost

Diabetes
$413 Billion		Smoking
$240 Billion		Heart & Stroke
$233 Billion		Obesity
$173 Billion		Lack of Leisure-Time
Physical Activity
$192 Billion		Five Category
Total
$1.25 Trillion
Number of PeopleCostNumber of PeopleCostNumber of PeopleCostNumber of PeopleCostNumber of PeopleCost
Total27,335,314$413 Billion37,168,647$240 Billion22,859,444$233 Billion86,702,629$173 Billion60,516,058$192 Billion$1.25 Trillion
Group A11,796,180$178,224,490,814 15,718,686$101,496,417,528 9,874,252$100,645,520,802 37,044,611$73,916,071,445 26,390,998$83,731,026,226 $538,013,526,815
Group B15,539,134$234,775,513,976 21,449,962$138,503,582,472 12,985,192$132,354,479,198 49,658,018$99,083,928,555 34,125,060$108,268,973,774 $712,986,477,975
Difference, Group B-A3,742,954$56,551,023,162 5,731,276$37,007,164,943 3,110,941$31,708,958,396 12,613,407$25,167,857,111 7,734,062$24,537,947,548 $174,972,951,160
B/A Ratio1.31.41.31.31.31.3
Per Person Annual Cost$15,109 $6,457 $10,193 $1,995 $3,173 $6,337
% of Group B
That Can Directly Benefit		5.9%9.1%5.7%7.5%4.1%6.4%
People Directly Benefiting911,600$13,773,055,6161,958,500$12,646,142,201740,900$7,551,789,151 3,721,900$7,426,403,415 1,399,700$4,440,844,451$45,838,234,834

Whether we look at particularized details or broad graph views, the consistent message is that the dark mornings coming through DST and inappropriate time zones (DST-TZ) produce huge and unnecessary medical expenses to the tune of many billions of dollars. In these graphs, we can see the advantage of low Group A values, substantially equivalent to permanent standard time.
Heart Stroke_Cost Obesity Cost

Lack of Leisure Time Physical Activity Cost The nesting ground for harm is Group B. That group should not exist at all. By the stroke of a pen, it could be eliminated. In the five categories here, already $713 billion is annually being spent in Group B, when a direct $45.8 billion saving should have prevailed instead. About 6.4% of Group B in these five categories will suffer from direct chronic disease brought on by DST-TZ. From DST-TZ, many more of us will endure low-grade, subpar feelings, short of a chronic disease fully expressing itself. If you live in a group B region, there is no reason to further endure DST-TZ damage year after year. But given the history of the past 60 years, the flimsy twaddle that supports continuous DST-TZ may again be sufficiently effective to guarantee that, throughout your life (if you are a Group B resident), you will not be at the top of your game.

Self-Harm & Dark Mornings

It is hard to even imagine, but it appears that the sun's light-dark cycle is also influencing our behavior to the extent that we see more suicides with high levels of dark mornings.

More suicides with dark mornings Note: The data in above graph is pure, unsmoothed, centered rolling average. Each datapoint is supported by 700 counties. Source: DM spreadsheet v2.0 & http://wonder.cdc.gov/ucd-icd10-expanded.html. To reduce confounding elements, limited data to white race. 2,460 counties available and used.

Beneath the 37% Threshold the average indexed rate of suicide is 102.7. Above the threshold it is 107.5, an average difference of 4.8%. This increase is roughly in the same range as in the DM Chronic Disease Model table: Depression, 5.8% increase; Mental Health, 4.0% increase.

In these three areas, dark morning's impact on our wellbeing is plainly adverse and unnecessary.

In contrast, the graph pattern seems to suggest a noticeably protective effect when dark mornings are between 29% and 32%, a range which elsewhere we have also seen to be healthy.

Mood

Question: Do seasonal DST-related dark mornings influence dopamine and mood? Google AI Overview Response: Yes, seasonal Daylight Saving Time (DST) dark mornings, particularly in the spring, significantly impact mood and brain chemistry by disrupting circadian rhythms. Reduced early morning light lowers production of serotonin (mood-boosting) and can disrupt dopamine (motivation/pleasure) levels, leading to increased fatigue, irritability, lower energy, and depressive symptoms. Key Impacts of Dark Mornings (Spring Forward):
  • Serotonin & Dopamine Dip: Lower morning light exposure decreases the release of serotonin and hinders optimal dopamine production, affecting mood regulation and motivation.
  • Melatonin Disruption: Darker mornings, coupled with increased evening light, can cause melatonin production to start later, making it harder to wake up and causing significant grogginess.
  • Mental Health Effect: The abrupt, one-hour change in the spring can cause 11% more reported depressive symptoms. This happens because the internal body clock is mismatched with the external social clock.
  • Physical Symptoms: The combination of sleep deprivation and lower light can lead to increased fatigue, anxiety, and, in some cases, a higher risk of accidents.
…

Circadian Rhythm & Mood

Question: To what extent is mood influenced by circadian rhythm and Western Edge Effect? Google AI Overview Response: Mood is profoundly influenced by the 24-hour circadian rhythm, with disruptions like shift work or jet lag [desynchronization] causing increased rates of depression, anxiety, and bipolar disorder. The Western Edge Effect (later sunrises/sunsets on the western edge of time zones) exacerbates these issues, causing persistent, forced misalignment between social schedules and natural sunlight, impacting mental health. Key Findings on Mood and Circadian Rhythms:
  • Circadian Misalignment: Irregular rhythms (e.g., night-shift work) make individuals up to 40% more likely to develop depression.
  • Biological Basis: Disruptions affect cortisol levels, sleep-wake cycles, and brain neurotransmitters like serotonin.
  • Time of Day: Negative mood often peaks during the biological night.
  • Treatment: Correcting rhythms via light or dark therapy stabilizes mood, proving a direct causal link.
The "Western Edge" Effect:
  • Delayed Sunlight: People living on the western edge of a time zone experience later sunrises and sunsets.
  • Chronic Jet Lag [desynchronization]: The mismatch between local clock time and solar time causes a chronic state of, essentially, "social jet lag," which is linked to poorer mental health outcomes.
Extent of Influence: The influence is significant and bidirectional. While internal clocks dictate mood, external societal pressures (like DST and time zone boundaries) that disrupt these rhythms can trigger or exacerbate mood disorders in vulnerable populations.

Circadian Rhythm Disruption & Addictive Drug Use

Question: Is there a relationship between addictive drug use and circadian rhythm disruptions? Google AI Overview Response: Yes, there is a strong, bidirectional relationship between addictive drug use and significant circadian rhythm disruptions. Addicted individuals frequently experience severe sleep disturbances and desynchronized biological clocks. … Chronic circadian misalignment (such as from shift work or genetic predisposition) increases vulnerability to addiction and relapse. Key Aspects of the Relationship:
  • Bidirectional Disruption: Addictive substances (alcohol, opioids, stimulants) alter the expression of "clock genes," which control the body's internal timing, leading to sleep disorders like insomnia, hypersomnia, and restless legs syndrome.
  • The Vicious Cycle: Chronic circadian disruption acts as a stressor that makes individuals more vulnerable to seeking drugs for stimulation or relief, further damaging their internal clocks.
  • Impact on Brain and Behavior: Drug-induced disruption of the circadian system affects reward-related pathways in the brain, particularly dopamine signaling, which drives addiction, reward-seeking, and cravings.
  • Relapse Risk: Poorly regulated sleep and circadian rhythms are significant factors in high relapse rates.
  • Treatment Potential: Restoring circadian rhythms through regular schedules, light therapy, and behavioral changes is emerging as a critical component in treating substance use disorders.
An aside: The preferred, wide-scope treatment would seem to be to eliminate DST and improper time zones.

Teenagers

Adolescents who sleep for longer than their peers tend to have improved brain function and perform better on cognitive tests. The CDC recommended hours of sleep below change with age. Adolescents need considerably more sleep than fully matured adult brains. Most now get only about 6.5-7.5 hours sleep per night – far less than recommended hours.
Age GroupAgeRecommended
Daily Sleep
Newborn0–3 months14–17 hours
Infant4–12 months12–16 hours
Toddler1–2 years11–14 hours
Preschool3–5 years10–13 hours
School age6–12 years9–12 hours
Teen13–17 years8–10 hours
Adult18–60 years7 or more hours
Adult61–64 years7–9 hours
Adult65 years and older7–8 hours

To the question "Are teenagers influenced by dark mornings?" a Google AI Overview responded:

Yes, dark mornings significantly influence teenagers because their biological clocks (circadian rhythms) naturally shift during puberty, making them feel sleepy later at night and wake up later in the morning, so early darkness clashes with their needs, worsening sleep deprivation, affecting mood, focus, and academic performance, leading to "social jet lag" [desynchronization] and potentially higher risks for mental health issues like anxiety and depression.

How Darkness & Light Affect Teen Sleep

  • Delayed Melatonin Release: Puberty causes teenagers' bodies to release the sleep hormone melatonin later, turning them into "night owls".
     
  • Light is Key: Light, especially blue light from screens and early morning sun, tells the brain to stay awake, while darkness signals sleep.
     
  • The Morning Problem: Dark mornings mean less morning light exposure, delaying the brain's wake-up signal and making it harder for teens to feel alert, even after sufficient sleep.

Impacts on Teenagers

  • Sleep Deprivation: Teens need about 9.5 hours of sleep but often get less due to early school starts, leading to chronic tiredness.
     
  • Performance Issues: Lack of sleep and delayed rhythms can cause poor memory, difficulty concentrating, and lower test scores.
     
  • Mental Health: Sleep deficiency exacerbates stress, increasing risks for anxiety, depression, aggression, and rule-breaking.
     
  • Social Jet Lag [desynchronization]: The mismatch between their biological clock and social schedules (school) creates a constant state of jet lag, affecting mood and health.

For teens DST-TZ is deplorable, harmful, and unnecessary. A huge gaping error.

State By State, the price we pay

Dark mornings degrade performance. We tend to have more personal income when we have few dark mornings. As it stands, only the lucky few counties (at the right on this graph) are beneath the DM Threshold & exceed the indexed median at 100. At the median, their group is 1.3% higher.
Dark Mornings Degrade Per Capita Income
Note: The data in above graph is pure, unsmoothed, centered rolling median. Each datapoint is supported by 900 counties. Source: DM spreadsheet v2.0 & https://www.bea.gov/data/income-saving/personal-income-county-metro-and-other-areas . Average of 2021, 2022, 2023 incomes used to represent the general average.
In state-by-state fashion this is what we see:
Dark Morning - Income Impact
Here, using the data in the following table, relative to percentage of dark mornings, we have personal income indexed to a median 100. The trendline shows data that now exists, with income being lower when dark mornings proliferate, and being higher when there are few dark mornings. This implies a low percentage of dark mornings enabling elevated personal incomes and conversely foregone income predominating when there are a high percentage of dark mornings. State by state, the table and graph show the influence of DST-TZ. With them, we have state-level data created by averaging all counties in each state. The first seven states are the most extreme. Due to overreachingly inappropriate time zones, their delays exceed 30. These high delays produce excessively dark mornings ranging from 57% to 65%. At a 98 indexed personal income, the average income for the first seven is 6.2% lower than the average for the rest of the states. By the time we reach an appropriate 8-delay sync point [37% dark-morning threshold], incomes for the first twenty-six states remain stuck at a 97 average. They are not even able to reach the median 100. The remaining twenty-three, low-morning-darkness states averaged a 13.4% higher income, index 110.
Table For Each State
StateDelayCurrent
Dark
Mornings		Dark Mornings With
Permanent
Standard Time		Average Delay
After Time-
Zone Fix		Dark Mornings
With Both DST
and Time-Zone
Fix		Household
Income		Per capita
Income		Ultimate
Personal
Income
1MI3865%40%96%949393
2IN3562%38%108%939393
3GA3461%38%108%979194
4TX3461%37%1514%101101101
5OH3159%36%1314%939594
6ND3158%36%88%105113109
7KS3057%35%1416%9710099
8OK2956%34%1720%869088
9UT2755%33%1822%11993106
10ID2553%32%710%958891
11NE2452%32%913%100105103
12SC2452%31%2229%888787
13AZ2452%31%1318%999396
14SD2351%31%712%96108102
15FL2350%31%1622%9310096
16WV2250%30%2230%768279
17KY2048%29%16%838584
18MT1947%29%1118%929794
19NC1846%28%1524%919392
20MN1846%28%1828%116111114
21VA1442%25%1324%121113117
22IA1442%25%1425%999798
23PA1039%23%1023%101107104
24MO1038%23%1023%919593
25WY1038%23%1023%103120112
26AR1038%23%1023%788481
… Threshold …
27DC837%22%822%139120130
28LA736%21%721%809286
29MD735%21%721%137119128
30OR735%21%721%103100102
31NM534%20%520%828584
32CA432%19%419%124122123
33TN332%19%-59%889491
34WA332%19%319%122160141
35CO331%19%319%120117119
36DE231%18%218%110102106
37NY231%18%218%112125118
38WI-128%17%-117%101100100
39MS-128%16%-116%747775
40NJ-128%16%-116%135128132
41IL-326%15%-315%108110109
42VT-920%11%-911%103105104
43CT-920%11%-911%127143135
44NV-1020%11%-1011%999999
45AL-1316%9%-139%828483
46NH-1416%9%-149%127121124
47MA-1416%9%-149%133138135
48RI-1416%9%-149%110106108
49ME-228%4%-224%959896
50Min-228%4%-224%747775
51Median1038%23%718%99100100
52Max3865%40%2230%139160141
[Table derived from DM spreadsheet v2.0 and Wikipedia Income Data: Median household income (2013 to 2023), Per capita personal income by state (2010 to 2023)] The income used here is the average of the indexed household and per capita personal income. The above chart is not shown for predictive purposes, but to illustrate current existing conditions. An R2 of 0.13 implies that 13% of the variance is explained by delay and dark mornings and the remaining 87% of the variance is unexplained.
As shown in the table, permanent standard time largely eliminates overly dark mornings. Looking at the Min-Median-Max section at the end of the table, we see a potential three-step, dark-mornings, repair process: Current Dark Mornings, then Permanent Standard Time, then Complete Fix.

At the max, this repair sequence produces: 65%, 40%, 30% dark mornings.
At the median: 38%, 23%, 18% dark mornings. Note that Arizona (row 13) would normally have averaged 52% dark mornings. But, by rejecting DST, its dark mornings are now safely reduced to 31%. People living there seem quite happy with it. By correcting time zones in La Paz, Yuma, Mohave, Maricopa, Pima, and Yavapai counties AZ could also further reduce their dark mornings to 18%.

Latest Sunrises vs. Permanent DST

Among the prior five DST options shown in the map tables, you can precisely see latest sunrise at your location. Permanent DST is option #5. In 5-minute steps, latest sunrises are condensed in this graph and table. Percentages indicate county percentiles experiencing shown sunrise times. Permanent DSTs have been widely rejected, "No country is currently on year-round daylight saving time."

Permanent DST A Disaster Compared To All Other Alternatives
Latest Winter Sunrises Vastly Later with Permanent DST
Percentile:2.5%10%25%50%75%90%97.5%AverageWaste
Permanent DST7:558:058:208:358:509:059:208:351:17
Current DST & Time Zones7:057:207:307:458:008:108:207:450:27
Permanent Standard Time6:557:057:207:357:508:058:207:350:17
Permanent Standard Time
& Fixed Time Zones		6:356:457:007:207:357:458:007:170:00

The primary threat is the possibility of Year-Round Daylight Saving Time. Effectively all of us (97.5% of counties) now have latest sunrise well before 8:20 AM, as shown in the table and highlighted in bold type. With permanent DST, this is turned on its head with only 25% of counties having latest sunrises before 8:20 AM. The US tried Permanent Daylight Saving Time in the ’70s. People hated it. An epic blunder. Congress rescinded it. A plainly appropriate rejection. If you require further evidence, please just ask the question: "Is permanent daylight saving time healthy?"

Adverse Reaction to DST

Given the question, "Excluding fatalities and excluding the transition periods, do humans have an adverse reaction to Daylight Saving Time?" Google's AI Overview summarized:

Yes, humans can have an adverse reaction to Daylight Saving Time (DST) even outside of the transition periods, due to the misalignment it creates between the body's internal clock and the social clock. The shift to DST in the spring pushes more daylight to the evening and reduces it in the morning, which disrupts the body's natural circadian rhythms.

How circadian misalignment affects the body

  • Waking up in darkness: The lack of morning sunlight delays the signal for your body to wake up and produce cortisol, the "stress hormone" that helps you feel alert. This can lead to increased grogginess and sleepiness.
  • Later melatonin release: The increased evening light from DST pushes back the production of the sleep-regulating hormone melatonin, making it harder for many people to fall asleep at their usual bedtime.
  • Chronic sleep deprivation: This combination of later melatonin production and fixed social schedules (work, school) can lead to chronic sleep loss throughout the DST period.
  • "Social jet lag" [desynchronization]: Sleep experts call this ongoing misalignment between the body's internal clock and social schedules "social jet lag." It can lead to long-term health problems.

Adverse health effects linked to DST
Research shows that chronic circadian misalignment during DST is linked to a variety of long-term health issues:

  • Cardiovascular disease: Studies have linked the chronic effects of DST to an increased risk of heart disease.
  • Metabolic disorders: Problems like obesity and diabetes are associated with ongoing disruption to circadian rhythms.
  • Mental and cognitive health: Chronic sleep loss can contribute to mood disturbances like depression and anxiety. A Stanford study found that year-round standard time would prevent more cases of depression and suicide than year-round DST.
  • Digestive issues: Some studies show a link between DST and immune-related digestive problems, such as colitis.
  • Lowered immunity: Insufficient and poor-quality sleep, a common side effect of DST, can weaken the immune system.

Who is most affected?
The impact of DST is not uniform across the population. Some individuals, and particularly specific groups, are more vulnerable to its effects:

  • "Night owls": People who naturally prefer to go to bed and wake up later often struggle more with the shift to DST.
  • Western edge of a time zone: Residents on the western side of a time zone, who experience a later sunrise and sunset, may have greater circadian misalignment and higher rates of obesity, diabetes, and cardiovascular disease.
  • Adolescents: Teenagers' biological clocks naturally shift toward a later sleep-wake cycle. When DST forces them to wake up even earlier for school, their sleep deprivation is significantly worsened.

Key DST Desynchronization Studies

The Question: What are the primary desynchronization studies and source material for DST and broad time zones that span more than 15 degrees of longitude? Google AI Overview Response: Primary desynchronization studies regarding Daylight Saving Time (DST) and broad time zones (those exceeding the standard 15° of longitude, such as in China, Spain, or the western edges of US time zones) focus on the misalignment between the social clock (time on the wall) and the biological clock (circadian rhythm). These studies generally conclude that the human circadian system struggles to adapt to DST, leading to "social jet lag" [Desynchronization]. Key Desynchronization Studies & Findings
  • Circadian Mismatch & Health (Weed et al., 2025): A major Stanford Medicine analysis in the Proceedings of the National Academy of Sciences found that changing clocks twice a year disrupts circadian rhythms, leading to higher rates of stroke and obesity. It suggests that permanent standard time is healthier than either annual switching or permanent DST.
  • The "Western Edge" Effect (Roenneberg et al., 2019): Studies indicate that people living on the western edge of a time zone (where the sun rises/sets up to an hour later than the center) have higher rates of cancer, obesity, diabetes, and heart attacks. This is because their social schedule is effectively forced to start earlier in the day than their biological clock prefers.
  • DST and Circadian Entrainment (Kantermann et al., 2007/2008): Research, including a study of 55,000 subjects, showed that while humans adjust to the east-west progression of dawn, the human circadian system does not adapt to the artificial time change of DST in spring.
  • Impact on Adolescents (Malitz, 2024; Gaski & Sagarin, 2011): Studies on DST and scholastic performance show that the 1-hour shift negatively impacts students, particularly in the western regions of time zones, with increased rates of delayed sleep phases.
  • Geographical Discrepancies (Arguelles-Prieto et al., 2024): A study using wearable devices found that transitioning to DST disrupts circadian markers more than transitioning back, corroborating that the spring shift causes a 1-hour discrepancy that persists for weeks.
Core Source Material & Research Focus
  1. Sleep Research Society & AASM: The American Academy of Sleep Medicine (AASM) has published position papers (e.g., 2020, 2024) advocating for the elimination of DST in favor of permanent standard time, citing evidence that the latter better aligns with human biology.
  2. Chronobiology Studies (Roenneberg, 2019): Work by Till Roenneberg and colleagues on "social jetlag" is fundamental to understanding how time zones that are too broad (e.g., China's single zone, or UTC+1 in Spain) create chronic, long-term desynchronization.
  3. Cancer Epidemiology & Longitude (Surveillance, Epidemiology, and End Results Program data): Studies using this data show a correlation between increasing distance from the eastern border of a time zone to the western border and higher cancer rates.
  4. Math/Circadian Modeling (Jewett-Forger-Kronauer model): Researchers use this model to simulate human circadian rhythms in response to light, confirming that the spring transition causes prolonged desynchronization.
Key Concepts from Studies
  • Social Jet Lag: [Desynchronization] The chronic misalignment between biological time and social time.
  • Light as a Cue (Zeitgeber): The disruption of natural light cues in the morning during DST causes the body clock to remain out of sync.
  • Western Edge vs. Eastern Edge: Living in the west of a time zone creates a "permanent" 1-hour delay in the biological clock compared to the east.

For the Nation, A Common Experience

In their unadulterated state, without DST-TZ, dark mornings by natural means are absolutely capped at a 37% maximum for all counties in the continental United States. In a vastly different fashion, most of us are now stuck in long seasons of artificial, human-created morning darkness. In the United States, as evidenced by the red curve, we now are living in widely different levels of darkness. These red-curve locations have disproportionately more dark mornings than conditions represented by the other curves. Had we chosen to live in substantially natural time, all of us would experience roughly similar days at a median 19% dark mornings. But now, as a nation we do not have this basic common experience. The spread between us is artificial, unnatural, and large.
Time zone DST Dark Morning Options [Spreadsheet notes: This graph is from spreadsheet v2.0 and based on formulas and a prior graph.]
The wide range of red-curve DM values signifies extreme seasonal changes in morning sunlight. That means one thing: an enormous circadian burden. On the other hand as you can see in the red curve, the natural median, at 19% DM, is rarely achieved. Going to this healthy level has an extremely low circadian burden. Most of us, in the United States, in our entire lifetimes have never seen sensible, natural seasons of morning darkness. The greatest deviations have occurred when delays exceeded 30. For this group of counties, the current DST and time zones dark mornings have ranged from 57% to 83%, shown in the dark red curve. For this group, had long DSTs been abandoned, dark mornings would have instead ranged from 35% to 52%, as shown at the orange curve. The most benefit occurs when both DSTs and time zones are repaired. In this instance, green-curve dark mornings drop to trivially low levels for the counties now having 30+ delays and many dark mornings. For those of us living in reasonable time zones with delays lower than 30, but burdened by excessively long DSTs, our dark mornings drop, after the repair, to the graph's green curve. With the green curve, we together reach a narrow, natural band of optimal morning sunlight. The dashed green-line at a 19% median expresses the overall outcome of the DST-TZ fix. With it we arrive at a common nationwide experience. An experience which, relative to the median, comfortably falls within a narrow ±19% range for all Americans. In polar opposite fashion, we now are closer to a wide ±44% range. The difference is unnecessary.
 

The Potent 8-Delay Sync

As we later see, across many health and economic categories, the pivotal influence of the 8-delay sync factor stands out [36% DM]. So long as sync is equal to or lower than the 8-delay, we tend to have superior performance. But when desynchronization exceeds, especially greatly exceeds, the 8-delay, top performance is suppressed across many categories. Who would have thought it? It turns out that the 8-delay sync is the median natural delay. Instead of the current delay's median, this is the point to which we gravitate to get superior performance. We find it at the median in this table.
County
Percentile		Current
Delay		Natural
Delay		RatioCurrent
Dark
Mornings		Natural
Dark Mornings
After DST
and Time-Zone Fix
2.5%-16-161.014%0%
5.0%-13-131.016%1%
10.0%-8-81.022%2%
15.0%-4-41.025%3%
20.0%-1-11.028%5%
25.0%312.231%7%
30.0%632.334%8%
33.3%832.236%10%
40.0%1152.240%13%
45.0%1472.142%15%
Median
50.0%		1882.245%17%
55.0%2192.249%19%
60.0%24112.252%21%
65.0%27122.254%22%
70.0%30142.157%24%
75.0%32171.962%28%
80.0%34191.859%26%
85.0%37221.764%30%
90.0%40251.666%32%
95.0%43271.670%33%
97.5%46291.673%34%
[Table derived from DM spreadsheet v2.0.]
At no point is the current delay better than the natural delay. As especially seen at the median point (50%), by going with a natural delay distribution, health and economic benefits are more widely spread. Explicitly, 8-delay benefits grow from 33.3% to 50% of the nation benefiting from them. When we also take trendline percentages of current dark mornings and fixed time zones & DSTs into account, we find that percentage of dark mornings are readily controllable. Simply returning to DST & time-zone natural states performs the fix, as the right-hand column's 34% or lower dark mornings show. Via the natural delay distribution, all Americans have appropriate morning sunlight and its attending benefits.

The DST Fiasco. A Failure to Crop the Wings.

The current DST is a misshapen bird. Its body (June through August) does the work. Its wings (March through April and September through October) do the damage. Current DST is active for two-thirds of a year. Half of that time — one-third of a year — is spent in destruction. "Abolish DST?" … Or just, "Crop the Wings?" Eastern positions within a time zone increase seasonal morning sunlight. Exacerbated by improper time zones, western positions decrease it. Lawmakers in Washington, DC see vastly different conditions than the nation as a whole. For example, Terre Haute in Vigo County, IN is about 260 miles further westward than is appropriate for its time zone. When, on the map, you move your cursor due west from Washington, DC to Vigo (both are nearly at the same latitude), you go from 38% of early mornings being dark in Washington to 70% being dark in Vigo. Washington and cities on the East Coast consistently have far fewer dark mornings than experienced on the western edges of time zones. As for a fix, it is generally unknown that when its time zone is repaired to more closely approximate natural time, Vigo will have only 20% dark mornings – far better than the vast majority of counties on the East Coast, better than the 24% in Santa Barbara, CA, and about the same as at Harvard University and MIT. Similarly, it is generally unknown that when, instead of the current DST, Permanent Standard Time or a short Memorial to Labor Day DST is also employed in Vigo, only 13% of mornings will be dark. Only three counties on the East Coast can now claim this honor. For Vigo to get there requires a two-step process: 1) repair time zone, and 2) trim DST’s wings to a short period. The three interactive maps on this page make this clear. Without the wings and without improper time zones, there is no inappropriate increase in morning darkness. DST Wings As shown in the graph, quickly rising morning temperatures in Vigo come between 7:00 AM and 10:00 AM, with peaks occurring by about 4:00 PM. In Vigo, the current DST starts on March 10 with a typical three temperature sequence of: 35°, 41°, and 49°. The cool/cold wings shatter the myth that the current DST is predominantly a summertime experience. A corrupted time zone or a long DST makes early mornings darker and colder. When DST-induced darkness and coolness are confined to counteracting a short period that already has abundant early morning sunlight and high temperature, the DST appears to be passably harmless. But when, as with the current DST, this darkness and coolness is widely spread over many already cool and dark months, the percentage of dark and cold mornings escalate. The wings do the damage. The Memorial to Labor Day DST has no wings. At 7:00 AM, it begins and ends at 60° in Vigo. By contrast, the current DST has long wings. It contains 71 more Spring days (March to May) and 55 more Fall days (September to November) than the summertime-only Memorial to Labor Day DST. Why have the wings?? They are useless. At a total 126 days, they are even longer than the 113-day summertime-only DST. These 126 additional days of Daylight Saving Time raise obvious warning flags, given that they all occur during school months when early morning cognition and school bus safety are issues. By skirting harmful aspects of long DSTs and by having a low percentage of sunrises after 7:00 AM, a Memorial to Labor Day DST is a winner, as is Permanent Standard Time.
[Spreadsheet notes: Temperature, Vigo County, IN. US Hourly Climate Normals (2006-2020).]
 

DST's Pitiful Wings, Waste & Destruction: Oct, Mar, Apr, Sep.

The damage done by the current DST is done at the wings. We need to focus on that portion of the DST. It has no health or economic benefit. Glowing claims of the current DST's economic advantage are routinely made. Stats don't match. The frequent claim that the current DST drives retail sales is misleading. At best, the influence is small. The winged months of October, March, April, and September are some of the worst retail months … a 122-day DST waste. As for a possible countercyclical advantage, the retail oscillation that might prove useful is to begin a DST at the rare peak on or about May 20. Yes, there are seasonal patterns, but month to month deviations are commonly small without a pattern sufficient to claim that the current DST improved the economy. We should not be surprised. In the fourth quarter, retail constituted a mere 6.3 percent of GDP.
Tail now wags dog. Retail Oscillations During Current DST

Ranked Retail Sales Relative to Average Month
Month Rank 1993-2019DST #3, 1993-2006DST #4, 2007-2019
Dec124.5%28.4%19.9%
Nov23.6%3.7%3.5%
May32.7%1.8%3.7%
Aug41.5%1.2%1.8%
Jun5-0.6%-1.1%0.0%
Oct6-0.8%-0.8%-1.0%
Jul7-1.0%-1.7%-0.1%
Mar8-1.8%-3.3%-1.0%
Apr9-2.9%-3.2%-2.6%
Sep10-4.5%-4.4%-4.6%
Jan11-10.3%-11.0%-9.5%
Feb12-12.5%-13.2%-11.5%
.
Oct, Mar, Apr, Sep-2.5%-2.9%-2.3%
Aug, Jun, Jul0.0%-0.5%0.6%
[Spreadsheet notes: SRS1 Cubic Spline converts centered monthly retail sales to daily rates.]

Retail sales. Tip of iceberg.
We are well served by turning our attention to the remaining, non-retail, 93.7% of the economy. Most economic activity occurs entirely outside the retail sector.  Via circadian channels, appropriate exposure to early morning sunlight influences health, alertness, mood, and cognitive abilities. A failure to take advantage of morning alertness in the non-retail sector is a foregone opportunity. To compromise morning hours of sunlight by indiscriminately taking one hour from them, and thereby increasing morning darkness, comes at a large expense to the economy. Alertness and quality of decision-making during these hours are crucial for economic success.

Seasonal Darkness Indicates DST Economic Impact [Spreadsheet notes: 3,093 counties, current DST and time zones. Based on Centers for Disease Control and Prevention Pre-COVID database, Social Vulnerability Index 2018. Total_Personal_Income= Per_Capita_Personal_Income *Population. Data sorted to Percent_Days. Index= Centered rolling 200-point median/ column_median* 100. Index smoothed on 30-point centered moving average. Not required here but used elsewhere: Proper Delay= MOD(ABS(longitude) *4+30,60)-30.]
Peak economic performance responds to percentage of days with early morning darkness. The approximate breaking point for success appears to occur at 51% of mornings being dark. Before that point, great successes occur. After it, no bursts of favorable economic tendencies appear. At high doses of gloomy mornings, median index values in excess of 100 rarely happen. Under normal, unadulterated conditions all of the counties that now exist to the right of the improper time zone marker would be on the far left-hand side of the graph and be able to enjoy the advantages of low delays. Instead, by the stroke of a pen, they are now stuck at the far right in the most disadvantageous position. Peaks at 30%, 38%, and 46%. Red flag at 51%: Per Capita Personal Income appears highest at about 30% dark mornings, which roughly corresponds to a 2-delay. At this point we are at our peak and in sync. At our worst, with dark early mornings higher than 51% [a 23-delay], our performance typically ranges from substandard to punishingly destructive. Areas to the right of the improper time zone marker are especially hard hit. Population data shows a decline with a high percentage of gloomy mornings — perhaps nice places avoided because their mornings were made less attractive than in the majority of the nation. It is striking when studying the U.S. News & World Report’s 2024 Healthiest Communities list (with a metric that equally values equity, vitality, and overall rank) how many nice, unrecognized midwestern counties percolate to the top. There is a pressing need for economists to seriously look at dark morning data. Entire regions are harmed by the fiction that manipulating DST and time zones far from their natural conditions is beneficial when, in fact, the data shows that the economic impact is devastating.
 

It is Not Only Economics. It is Life Expectancy.

The following is definitive. A tight link exists between delay (as in the Western Edge Effect) and longevity. The dark mornings that come with DST-TZ pack a wallop. The dotted background illustrates high variability when using only modest smoothing. Notwithstanding, we can make a solid analysis because we know: 1) delays for each county, 2) life expectancies for each county, and 3) at each point, we are consistently dealing with a large 900-county group, equivalent to improper time-zone group size.
Improper Time Zone Worst Longevity [Spreadsheet notes: Life expectancy estimates 2000-2019, both sexes. High accuracy life-expectancy data to
fraction of a year. To reduce confounding elements limited data to white race.]
With these three, we can see how equivalently-sized, centered 900-county groups would perform throughout the United States. Large group size gives high accuracy. Fifty-three million people live in improper US time zones. The influence of moving from improper time-zone positions to a median performance is equivalent to a 34.6 million person-year improvement [=53*0.653]. With all of the data together, we find: Best performance occurs at 4-delay and 6-delay [33% to 35% dark mornings]: 78.3 years.
Median performance occurs at 15-delay and 17-delay [43% to 45% dark mornings]: 77.7 years.
Worst performance occurs at 37-delay [64% dark mornings]: 77.1 years, solidly at the center of the corrupted time-zone group.
The difference between maximum and minimum: 1.24 years, 65.5 million person-years.

The difference between the median and the improper time zone group: 0.65 years, 34.6 million person-years. The science flows along the same lines when we ask, "From a circadian perspective, is there a relationship between delay and longevity?" Again, improper time zones make a difference. Massively unnecessary and harmful.
 

AI Shows Summertime-Only DST Clock Change To Be 5x More Desirable

Quoting ChatGPT we find that: Based on both a quantitative analysis and broader understanding of human circadian rhythm and societal patterns, it is reasonable to argue that a short DST beginning on May 20 would be significantly less objectionable—by a factor of around 5.3—than a traditional long DST starting in March. Here's why:
Quantitative Case: Sunrise Shifts & Longitude Translation
  1. Sunrise change over 30 days:
    • Short DST (May 20): 8-minute earlier sunrise over 30 days.
    • Long DST (March 10): 42.7-minute earlier sunrise over 30 days.
    • This means sunrise times are much more stable around the May 20 period.
  2. Translation to geographic equivalence
    • 1 minute of sunrise change ≈ 13.5 miles of longitudinal shift.
    • So:
      • Short DST = 108 miles
      • Long DST = 576 miles
    • That’s a 5.3x difference—suggesting that the long DST shift is equivalent to a forced "geographic relocation" that's over 5 times as jarring.
Biological & Circadian Implications
Social and Practical Considerations This would increase acceptance and decrease complaints, making it less controversial.
ChatGPT Conclusion: Shifting to a short DST beginning on May 20 would likely be around 5.3 times less objectionable than a traditional early March DST, both in terms of biological impact and public sentiment. The more stable sunrise times, reduced circadian disruption, and greater societal alignment all support this.
 

Summertime-Only
A Celebration of Summer
A Memorial to Labor Day DST
The Unofficial Start and End of Summer

Prior to the 1966 Uniform Time Act, Iowa and Minnesota practiced a Memorial to Labor Day DST. The Congressional Record shows that as late as 1985, the American Farm Bureau policy was, "We support legislation limiting daylight saving time to the period between Memorial Day and Labor Day." And, "We continue to support the right of a state to exempt itself from daylight saving time." The old Farm Bureau policy was wise. As the Kentucky Farm Bureau wrote in 1971, the Memorial to Labor Day DST is a reasonable way to alleviate problems created by daylight saving time. As a compromise, it will not satisfy everyone but it may go a long way toward resolving conflict. Similar to a US Memorial to Labor Day DST, between 1948 and 1952, Japan adjusted its clocks for summer, starting DST in May and ending it in September. After the US occupation ended, Japan abandoned the practice. Let’s look at median western-edge times prior to applying a long or short DST. In the following table, “Proximity” is sunrise relative to a 7:00 AM wake-up. For a sunrise to stay clear of a 7:00 AM wake-up, proximity at the start of the DST must exceed 60 minutes. Given this, and with improper time zones, a DST should never begin (or be active) prior to April 28. A Memorial to Labor Day DST is safely wide of this mark. Its proximity is at 1:45 hours. Sunrise is at 5:51 AM. Mornings are long, 7:11 hours. By this time in late spring, morning sunlight is changing very slowly. It will take 32 days for sunrise to occur 8 minutes earlier. This DST provides plenty of winter early morning sunlight for circadian entrainment. To initiate a DST on May 20 will reduce morning hours by a modest 14%. Many of those hours occur when we are fast asleep.
# Day Date Event Sunrise Morning Hours DST % of Hours Proximity
1 Jan 1 New Year 7:46 AM 4:46 21% -0:46
69 Mar 10 Current DST Start 6:48 AM 5:51 17% 0:11
140 May 20 Memorial Day 5:14 AM 7:11 14% 1:45
172 Jun 21 Longest Morning 5:06 AM 7:25 13% 1:53
252 Sep 9 Labor Day 6:06 AM 6:20 16% 0:53
308 Nov 4 Current DST End 6:58 AM 5:15 19% 0:02
[The above is based on NOAA spreadsheet, where a median latitude is employed at a conventional western edge
border (latitude 38.3°, longitude -82.5°, time zone -5, delay 30 minutes, local solar times prior to DST adjustments)].
While we sleep, it makes good use of some of the abundant May 20th very early morning hours. We still have 6:11 morning hours of sunlight remaining after one hour is taken away for a Memorial to Labor Day DST. Similarly, after exiting it in September, 6:20 hours of morning sunlight remain. With an eye toward practicality, it begins a week before and ends the week after heavy holiday transportation demands. Perhaps paramount for many, it happily blends with the tradition of Memorial Day being the unofficial start of summer and Labor Day being the unofficial end of summer — a bona fide summertime-only DST. An opportunity to catch the wave at the instant of high retail sales. High resilience/low death rates. A cresting of sunlight hours. A celebration of summer. By contrast, the current DST March 10 start date fails on all points. Sunrise, late. Proximity to sleep hours, harmful. High seasonal mortality. No social buoyancy. Morning sunlight hours, short. Long DST pointless — in the spring, morning and evening sunlight already increasing at a nice pace with standard time. Because of the 1966 Uniform Time Act and long DSTs, we never experienced in our lifetimes the natural unfolding of spring. With the prior gradual increase in sunlight, we safely and pleasurably could adapt over a period of about 55 days to 60-minute natural increases in morning sunlight. Instead, long DSTs gave us a three-part spring cycle: It is no wonder that changing clocks became hateful. Had the changings brought forth happy and beneficial events, we might well have gladly welcomed them. Instead, every March, completely without social buoyancy, we submitted to this pointless, harmful exercise.
 

Formulas For Delay & For Estimating Percentage of Dark Mornings

Appropriate time-zone boundaries occur at a 30-minute delay. In a one-hour time zone (60 minutes, with two 30-minute sections), the delay should fall within a ±30 minute range. It frequently does not. If you would like to calculate delay or percentage of dark morning trendlines on your own, you can do so.
In a spreadsheet solar delay as used here equals
(ABS(longitude)/15- ABS(time_zone_integer_hours_from_Greenwich)) *60
[Respectively -5, -6, -7, -8 integer hours for EST, CST, MST, PST time zones.]
With the current DST, Percentage of Dark Mornings =
28.84+(0.94955*Solar_delay); Smoothed Data Standard Deviation 2.6; R2=0.977
28.88+(0.94756*Solar_delay); Raw Data Standard Deviation 5.4; R2=0.909
With a Memorial Day DST or Permanent Standard Time, Percentage of Dark Mornings =
16.98+(0.59967*Solar_delay); Smoothed Data Standard Deviation 2.2; R2=0.959
17.02+(0.59877*Solar_delay); Raw Data Standard Deviation 4.8; R2=0.835
Here some trendline points are calculated for you, and in DM spreadsheet v2.0 they are calculated for each county in the continental United States. Simply told, on the current DST trendline, delay vastly increases number of dark mornings. In every year, improper Time Zones (30+ delay) deliver 81+ needlessly dark mornings. At the individual delay levels in this table, the current DST routinely delivers 1.66x as many dark mornings as Permanent Standard Time or a short DST. Over and above Standard Time days, the "Additional Needlessly Dark Mornings" column shows the number of additional mornings that in each year are now needlessly dark with the current DST. With Permanent Standard Time or a short DST there are no additional dark mornings.
Percentage of Dark Mornings
DelayCurrent DSTPermanent
Standard Time or
a Short DST		DifferenceAdditional
Needlessly
Dark Mornings
029%17%12%43
130%18%12%45
231%18%13%46
433%19%13%48
635%21%14%51
836%22%15%53
1038%23%15%56
1240%24%16%59
1442%25%17%61
1644%27%17%64
1846%28%18%66
2048%29%19%69
2250%30%20%71
2452%31%20%74
2654%33%21%76
2855%34%22%79
3057%35%22%81
3562%38%24%88
4067%41%26%94
4572%44%28%101
5076%47%29%107
5581%50%31%113
Delays in excess of 30 are caused by corrupted time zones. With them and the current DST, the number of gloomy mornings can explode to more than 80%. The current DST is inequitable. From this table we see that the current DST requires living in low-delay regions (such as 8-delay or less) in order to have few dark mornings [36% DM]. By this, it inescapably commits two-thirds of the nation to excessively long seasons of winter morning darkness. As we again see, this unnatural increase in morning darkness harms health and the economy.
 

Topics On This Page & Thesis Summary Show the Damage and Opportunity

Reviewing topics reveals the extent of DST and time-zone influence:
Digging Deeper
Reddit user provided this summary: Thesis Summary

University Rankings Uncover Underbelly of DST & Time Zones

U.S. News & World Report’s University Rankings provide a fine opportunity to evaluate low percentage of dark mornings at high-ranked universities. When we compare dark mornings in these microcosms of excellence to the 3,000 US counties, we see vast differences. These premier institutions have far fewer dark mornings than the general population. As to a university's purpose, cognition and maturation are central to the enterprise. Under circadian influence, maturation of the brain will continue until about age 25. With an eye toward determining levels of morning sunlight appropriate for cognition, university rankings are important to study. They seem to indicate that fewer dark mornings contribute to academic success. In the graph, we see a huge spread between the Top 10 universities and the common-case 3,000 counties. The Table shows that the current DST and its time zones, at the median, produce 47% dark mornings. A median percentage of darkness at 23% or less appears to be conducive to outstanding performance. A median higher than 30% seems to impede excellence.

Top US College, appropriate percentage of darkness
 Percentile:  2.5%  5.0%  10.0%  20.0%  30.0%  40.0%  Median 
 50.0 %		 60.0%  70.0%  80.0%  90.0%  95.0%  97.5% 
Percentage of Dark Mornings
 Time Zone/DST Fix 0%0%0%0%10%15%19%22%25%28%31%33%34%
Top 109%9%9%10%21%23%23%28%30%37%38%42%42%
Top 259%10%13%21%23%24%30%37%38%46%50%60%66%
Top 1009%10%16%23%23%28%30%38%43%50%60%65%67%
 All Counties, % Dark 3%8%20%30%36%41%47%53%58%62%65%68%70%
Minutes Delay
Time Zone/DST Fix-29-27-25-20-14-7061218252729
Top 10-16-16-16-15-10-8-4-12791214
Top 25-16-15-14-10-8-517916213239
Top 100-16-15-11-8-40281322323844
All Counties, Delay-16-13-8-151118243035404447
[Spreadsheet notes: Get ranked-order data and location. Convert location to longitude. By formula convert longitude to minutes of delay.
Convert minutes of delay to percentage of dark mornings using already established delay to percent relationships. Use Excel percentile formula
to produce graph and table. Data related to the fix come directly from original computer program. Note: In a perfectly symmetric ±30 time zone,
median delay is zero. Median delay at "Time Zone/DST Fix" comes close to this.]
In the US, only 20% of us live in zones that appear to be conducive to excellence by having fewer than 30% dark mornings. In a far more appropriate fashion, at the median the Top 10 universities operate at a mere 23% dark mornings. Commendable yes. But not remarkable!  More favorably, repairing time zones and DST gives us a median 19% dark mornings. With this, the entire nation, not just a select few universities, can have a low level of median morning darkness that is conducive to enhanced cognition.
 

The Essential Elements
Top Ranked Health … Payoff for Being in Sync … The 8 Minute Median

The influence of delay and morning sunlight may be subliminal and seemingly of slight influence, but that initial impression is misleading. Just as rankings uncover minutes of delay at universities, ranking health categories can also uncover median delays. In diverse health classifications, top performance is widespread at low median delays and few dark mornings. Being in sync matters. Morning sunlight is a key to health. First thing in the morning it resets body clocks. This is done daily. By comparison to artificial light, sunlight is especially effective because it is many times more potent. Dark mornings corrupt the resets. Consistent with this discussion, Google's AI points out: "Get bright light in the morning to feel more alert during the day." … "The sleep-wake cycle is incredibly important for overall health and well-being." Delay rules. With this simple handle, we can see the beneficial impact of morning sunlight. Desynchronization suppresses top performance. In this race, low delays are winners; high delays, losers. Like the Western Edge Effect, the lower the delay at your location, the more beneficial the impact. Quickly put: You get best circadian performance the closer you are to being in sync, which is to say, your location has a low delay. Beneficial circadian impact from the sun's light-dark cycle is surprisingly easy to spot. All you need to do is to look at median delay in a ranked category. In numerous categories, the following table tells what otherwise would be a complex story. Keep an eye on delays 8 or lower [36% DM]. Superior performance (Top 250 and lower) has a low median delay and increased morning sunlight, e.g., a delay that is 8 or lower as highlighted in the table. The emphasis is on the Top 250 counties (the top 8%). It provides a high-performance focus with an adequately large sample size. The further away delay is from this point, the weaker its grip. It is the beneficial influence of being in sync (low delays) that carries the weight. Using the median at Top 250 as an example: In a group of 250 counties, 125 counties are beneath the median; 125, above it. The delay segments that underlay these values are shown in the second half of the table to answer a natural curiosity about data that creates the rankings. In each of the categories, medians based on various portions of 3,000 data points carry considerable weight. Where you see only one number here, you do not see the many that support it. Most of the individual numbers in this table are backed by circadian features of 250 or more counties. The footprint of the light-dark cycle is large and, at the Top 250 level, often deep. Count yourself lucky if you live in a location with a low delay. Only 1/3 of counties now have a delay of 8 or lower. Unless there is change in DST and time zones, you are compelled to live in one of these counties to get the full extent of median 8-delay benefits. Effectively, by way of improper time zones and long DSTs, forced geographic relocations have already resulted in most counties being less healthy than they normally would have been. This table tells the story. In each health category, it shows median delays which now exist. By gradation, median delays in the table illustrate requirements for being suitably in sync at a range of rankings. As shown, requirements differ according to rank and category.
Each Health Category Shown in Rank Order, Top 50 to Top 3000. Corresponding Median Delays Shown at Each Level.
 ObesityDiabetesActivity
LPA		IncomeSmokingHeartStrokeDisabilityAverage
Combo-8		MobilityGeneral
Health		KidneyCognitionNo
Diploma		PovertyDepres-
sion		CancerRND
Top 50736598886.7981010911273111
Top 100418788886.4884101312273114
Top 250358888887.0999121414251518
Top 5007109991011119.4111213131415202019
Top 75081111121211131211.2121314141515201718
Mediocre
Top 1500		131415151514151714.8161514171617161618
Top 3000171717171717171717.0171717171717171718
Ratio2.41.72.01.91.91.81.51.51.81.51.41.31.41.21.10.90.90.9

Segments
Top 50736598886.7981010911273111
Top 50 to 100108786775.5711-1142114302715
Top 100 to 250288878897.310101215141722920
Top 250 to 500121411121213171613.3171519131517162319
Top 500 to 750131517222016181717.3141815151616191317
Mediocre
Top 750 to 1500		191721181918172218.9211614211818121619
Top 1500 to 3000222119201920201719.7192021171819171817
[Spreadsheet notes: Used CDC Places database and heading notes. For per capita personal income, diploma, and poverty used CDC Social Vulnerability Index 2018. In Excel matched delays with location. Sorted on CDC adjusted values. Calculated delay medians for counties at 50, 250, 500, 750, 1500, and 3000 group sizes. The RND column was created by putting delays in random order and then with the Excel Median function determining medians for Top ranks. The data in other columns derived their strength by the link between location and delay. Note: Statistical variability tends to be greatest in small sample sizes as evidenced by the RND column. Obesity graph, centered rolling 200-point median, smoothed on 30-point centered moving average.] In Top 250 ranked counties, Obesity, Diabetes, Activity, Per Capita Personal Income, Heart, Stroke and other categories typically have median delays of 8 minutes or less. This favorable performance often occurs at such delays and lower in the first eight categories (Average Combo-8) strongly suggests that circadian influence is simultaneously playing a broad role in many categories. The clear message is that a location being in sync is influencing numerous areas of daily life that are important. This is the way the table works: Each Top 50 rank contains the most advantageous characteristics in its category. Separately, its delay is the median of all its fifty counties. In this way, at each rank, median delay (the degree that a location is desynchronized) is identified. At each subsequent rank, median delay varies because that rank is less selective, because individual delays differ according to location, and because a larger number of data points are included. The table is instructive. When within a category a beneficial relationship exists, median delay increases when going from Top 50 to Top 3000 counties. If on the contrary there had been no influence, results would have looked more like the RND column. With this we have a quick, preliminary indicator of the influence of the sun's light-dark cycle. Strength of the patterns is often indicated by a high Top 3000/Top 500 ratio. Ratios higher than 1 tend to indicate a positive relationship. While many categories are favorably influenced by morning sunlight, all are not. Ratios lower than 1, or closely approaching 1, suggest randomness or a contrary relationship. The RND column (randomized delays) is an example of this. When a category's impact is not detected, it may appear here. For example, of fourteen categories, cancer had the lowest extent of change (1.1). Delay influence on obesity The method is simple, sensitive, and strong. Here by ratio, obesity is the highest ranked category for beneficial response from being in sync with the sun's light-dark cycle. Separately in another analysis, it is also the highest ranked category. Whether you look to sources on the web, on YouTube, or in scholarly literature, you will also find a potent link between obesity and circadian rhythms. For example, we see in the graph that with very low percentages of obesity, delays are low. But delays sharply increase when this percentage increases, as does the reduced morning sunlight that comes with this progression. Instinctively, it is surprising that a component like delay would have such a formidable influence on body weight. Along these lines, studies show morning sunlight does influence weight gain. Ratios in the table also illustrate relative strength in other categories. With the table you can get an intuitive feel for which health components tend to be most influenced by morning sunlight. For example, personal income, at a strong 1.9 ratio, draws attention to the light-dark cycle having considerable impact. But the influence seems to be less (low ratios) in the no-high-school-diploma and poverty categories, which are better observed elsewhere. Cognition at an intermediate ratio of 1.4 brings to mind the previously discussed college rankings. It is especially interesting that leisure-time physical activity (LPA), the second highest ratio here and similarly high ranking in a separate analysis, shows such a strong pattern of low median delays. This flies in the face of the contention that DST increases physical activity by creating an extra hour of afternoon sunlight. To the contrary, the table shows that low delays and more morning sunlight increase the amount of leisure-time physical activity!! Moreover, many components which create adverse headwinds for physical activity (obesity, reduced general health, et cetera) are augmented by the current DST's high delays and reduced morning sunlight. Routinely, the literature indicates that claimed exercise benefits from DST are at best modest and not universally supported.

Delay distribution before and after fix High delays come hand in hand with poorer outcomes. From the perspective of health and personal income, DST-TZ is a catastrophe. Top performing ranks have low delays. By living in a low delay location, a person can enjoy benefits in widespread categories. On the other hand, someone who lives in a high-delay area cannot enjoy this broad range of opportunity. They are stuck without a circadian boost to achieve high rank in a wide variety of categories. As illustrated in the graph, with the current DST and time zones, now only 34% of counties can deliver 8-minute delays. We are hamstrung. Fortunately, with a DST-TZ fix, 63% of counties can easily deliver 8-minute delays. If, for a county, your objective in a category is, for example, to perform at the Top 250 level in many categories, you typically would want your county to have a median delay equal to or less than the one shown in the table — an 8 minute median delay and 36% dark mornings seemingly being an adequate objective in many categories. To get to this point often requires a time-zone/DST fix. You see, delay is caused by your location. Beyond this, major changes in delay and features of the light-dark cycle must come from legislated components, specifically: time zones and DSTs.

Perpetuating DST Wings and Corrupted Time Zones.
For Top Performance Must Dump Them

To perform at a Top 250 level often requires that your location has a delay not higher than 8 or 36% dark mornings. We need to be clear. Low delays like 8 can be required for a Top 250 level of superior performance across many categories, the Combo-8 being just one example of widespread influence. Yet, with current time zones and DST, two-thirds of all counties are now completely unable!! to get down to the 8-delay or the 36% point, despite Top 250 levels of performance often requiring it. With this, they are more likely to be stuck at lower performance levels indicated in the table. Perpetuating DST wings and corrupted time zones prevents breaking through the 8-delay, 36%-barrier. Whereas, with the wings and corrupted time zones removed, literally every American has dark mornings capped at a 37% maximum, effectively equal to the current median 8-delay's 36%. For top tier performance, dark mornings must be greatly reduced. Details aside, being capped at 37% is the safe position. It works. It employs the same data used in the interactive maps. This sea change in many categories provides increased opportunity for a Top 250 level performance for all Americans, not just the lucky few now living at locations having an 8-delay median or lower.
 

Delay & Improper Time Zones Reduce Life Expectancy

With tip top life expectancy, we have a delay of 8. With high delays life expectancy is in the dumps, as we again see here, this time via the rankings. The previous table concentrated on delay's impact in health categories. Here we expand the picture to see life expectancy at birth worsening with increasing delays, especially very high delays. The first part of this table uses the same techniques as in the health rankings. Here we drill down into each segment, where we find the meat of the matter.
The potency of the full range of life-expectancy delays in this table is consistent with the General Health ratio of 1.4 in the previous ranked health categories. Table values sorted on life expectancy.
Life Expectancy & Delay
RankMedian DelaySegmentLife Expectancy
Median		Reduction
Per Step		Median Delay
Top 508Top 5083.78
Top 1009Top 50 to 10082.51.310
Top 25010Top 100 to 25081.51.012
Top 50012Top 250 to 50080.51.015
Top 75012Top 500 to 75079.60.913
Mediocre
Top 1500		15Top 750 to 150078.51.117
Top 300017Top 1500 to 300075.82.720
Ratio1.4 
Similarly in this graph, we find high delays at reduced longevity. For the 165 million people at segment delays 17 and 20 in the table, life expectancies plummet. Hand in hand, high delays come with reduced longevity. Again, high delays coming from corrupted time zones & the current DST contribute to an unfavorable outcome.
Delay and Longevity [Spreadsheet notes: Life expectancy estimates 2000-2019, both sexes. High accuracy life-expectancy data to fraction of a year. To reduce confounding elements limited data to white race. In graph, centered rolling 200-point median, smoothed on 30-point centered moving average.]
The deeper we look, the more we find that together with worsened health and reduced life expectancy come high delays. Being in sync matters.

Permanent DST and Seasonal Mortality

Sunlight influences death rates. Permanent Daylight Saving Time strikes hardest in winter months, precisely when we are most vulnerable. As shown in the graphs, throughout the year, death rates in the US and Japan move in the same pattern as hours of sunlight. Relative to the average, in seasons with more hours of sunlight there is a reduced tendency to die. Conversely, reduced sunlight increases that tendency. Subsequent to the shortest sunlight of the year (the winter solstice, December 21), death rates in the US and Japan lag sunlight by 28 days. Subsequent to the longest sunlight of the year (the summer solstice, June 20), the lag is an additional 15 days (a total 43-day lag during the summer half of the year). It appears that, directly or indirectly, the lags correspond to the cumulative impact of hours of sunlight exposure and that the additional lag in the summer reflects a protective effect of sunlight. The dashed lines are positioned to illustrate the exact outcome of these lags. Japan US Seasonal Mortality Mortality at DST Start
[Spreadsheet notes: Japan and US monthly death data, NOAA spreadsheet, SRS1 Cubic Spline to convert centered monthly death rates to daily rates, max morning sunlight hours scaled to max USA and max Japan death rates. A caution: Differences in amplitude do not imply differences in annual death rates or longevity. Amplitudes reflect only relative changes during a year, within a single country, during particular periods.]
It makes a difference when a DST starts. It should never begin or be active when people are most vulnerable. In the first graph, the current DST begins when death rates are 5.9% higher than the average. In a more suitable fashion, a Memorial to Labor Day DST begins when death rates are 3.9% lower than average. Seasonal death rates reflect healthiness and resilience. You would have to struggle to find a plausible date that is significantly less healthy than the current DST’s March 10 to start a DST. Except we now find Permanent DST to be even more shameful. In the second graph (in part an inverse of the prior graph), we see that a Memorial to Labor Day DST beginning on May 20 would start at a point 10.3% more resilient than the current DST’s March 10. Japan resides in a single time zone (UTC+9) that is reasonably aligned with solar time for most of the population. It does not employ a DST. It operates on Permanent Standard Time. For life expectancy, it frequently ranks as the top nation in the world. Its latitude (36.2°) is close to the US latitude (37.1°), thus similar sunlight. Japan’s green-curve mortality is instructive. Each year it goes through four distinct stages of death rate changes, approximately:
  1. A substantially linear reduction of death rates in the spring, Jan 28 to Jun 14 (138 days)
  2. A summer period with only slight changes in death rates, Jun 14 to Sep 17 (95 days)
  3. A linear increase of increasing death rates in the fall, Sep 17 to Jan 11 (116 days)
  4. A winter peak of death rates, Jan 11 to Jan 28 (17 days)
Closely matching the sunlight pattern, Japan's dominant features are its two pronounced linear wings on either side of a largely inactive summer period. Japan is also distinguished by, in middle June, reaching a narrow band of exceptionally low death rates beyond which increases in sunlight hours apparently become ineffectual. These shapes are presumably near optimum for a healthy nation. Japan's short 95-day summer period of highly stable low death rates is of special interest. This safe summer period overlaps 78% of the days in a Memorial to Labor Day DST, indicating a short DST's safety. The extent of seasonal variation in death rates correlates with latitude, with the greatest amplitude at mid-latitude around 35 degrees, as in the United States and Japan. Seasonality of mortality can be accounted for at high correlation levels [in thirteen nations: an average R2 of 0.922 for cardiovascular disease, 0.884 for all-cause mortality, 0.829 for deaths excluding cancer and CVD]. Paradoxically, northernmost countries, such as Finland and Canada, which have coldest climates, often display less seasonality than countries at less extreme latitudes, serving as a forewarning that causes remain uncertain. Regardless, we can see the seasonal death rates we must address, and do so — even when unsure about cause.
 

Human Seasonal Mood

A Google conventional search, “human seasonal mood,” produced this condensed AI Overview: Human seasonal mood changes often manifest as Seasonal Affective Disorder (SAD), a type of depression linked to reduced sunlight in fall/winter, causing low energy, sadness, and carbohydrate cravings due to disruptions in serotonin, melatonin, and circadian rhythms. … Why Does It Happen? (Causes) Common Symptoms Who Is Affected?

 

Circadian Impact on Real Estate, Towns, Cities, and Counties …
Dark Mornings Reduce Your Home's Value

In the following sections we turn attention to real estate, counties, and cities. Whether we look at cities in general or real estate in particular, we see that desynchronization has a measurable impact. This graph shows real-world median home values, which now apply.
Home Values Decline When Dark Mornings Increase [Spreadsheet notes: Census, American Community Survey, B25077 Median Value.
In graph, centered rolling 56-point median, smoothed on 9 point centered moving average.
Census reports 835 of all 3,000 counties; number of counties reported in this graph therefore scaled.]
Unknowingly, folks tend to pay a premium for homes with low delays and few dark mornings. To the surprise of most of us, as seen in the graph, your home tends to be worth more when it is at a location with few dark mornings and its value suffers when many early mornings are dark. Again, the greater the percentage of dark mornings, the greater the harm. Under natural conditions, at the median, about 19% of mornings are dark. When morning darkness brought on by improper time zones and long DSTs greatly exceed this figure, the trendline goes south, at an extreme point reducing median value by about $75,000. The reduction in value is not magic. With the current DST and time zones, the home value decline appears to be a downstream effect resulting from the extent to which locations are desynchronized. Delay derives its power from the many, not the few. At least a dozen key categories contribute to circadian impact. For example: General Health, Life Expectancy, Obesity, Stroke, Diabetes, Cognition, Heart, Personal Income, Leisure-Time Physical Activity, Disability, Kidney, and Smoking. Because delay influences so many categories, even if root cause is unknown, long-term impact is likely to be perceived and able to shape home values and opinions about a city's quality. The loss of home value is pointless. After all, before DST-TZ was invented, dark mornings, without exception, were naturally absolutely capped at a 37% maximum for all Americans. Locked at the 37% of dark mornings shown in the graph, harm would be removed and trendline price differences would tend to be acceptably small.
 

Flipping the Time-Zone/DST Incline … Low Delays Grow Population

Fully half the counties in the United States are small counties with populations less than 26 k (median delay 17.5), totaling 18 million people. The data shows that DST-TZ now thwarts their growth. Happily and surprisingly, circadian influence may be sufficient to produce foundational changes in small-county economic growth. Using data from the interactive maps, this table employs techniques similar to the life-expectancy rankings.
Ranked Population & Delay
RankMedian DelaySegmentMedian PopulationPopulation RangeMedian Delay
Top 5014Top 501,481 kmillion to 10 million14*
Top 1008Top 50 to 100820 k664 k to 958 k7
Top 2508Top 100 to 250402 k272 k to 664 k10
Top 50011Top 250 to 500172 k127 k to 272 k13
Top 75013Top 500 to 75095 k72 k to 127 k16
Mediocre
Top 1500		15Top 750 to 150042 k27 k to 72 k17
Top 300017Top 1500 to 300011 k2 k to 27 k21
Ratio1.5 
[*Note: The 14-delay in the million+ counties may be a normal consequence of high statistical variability in small sample sizes, e.g., Top 100 and Top 250 at an 8-delay are more stable than Top 50. The high 14-delay at the Top 50 city level may also suggest that components other than delay carry greater sway in million+ cities.]
For counties with populations less than a million, low median delays exist at high populations and high median delays exist at low populations. The differences are dramatic. A large county population (664 k to 958 k) has a low median delay of 7. A small county population (2 k to 27 k) has a high median delay of 21 — three times greater. With each step to a smaller population size, segment median delays (the degree to which locations are desynchronized) increase: 7, 10, 13, 16, 17, 21. Each of these steps to less favorable median delays come with reduced county populations. High population counties, by their size and delay, show a preference for living in low delay counties. Voting with their feet, folks seem to have been in part instinctively avoiding excessively dark & cold mornings and other direct and indirect unwholesome aspects of high-delay counties, thus congregating in larger low-delay counties. Independent of cause, the graphs show a migration incline moving from low to high population counties, from high delay to low delay, and from more dark mornings to fewer dark mornings. These reflect real world conditions that now exist. Delay and County Population Size Flipping Migration Incline
[Spreadsheet notes: For both graphs, centered-rolling 200-point median, smoothed on 30-point centered moving average.]
In the table and graphs, population is concentrated in large counties. The first graph shows a tendency toward low median delays at high county populations and very low populations at very high, way-out-of-sync median delays. Unknowingly the real estate business has been hammered by these high delays. Hand in hand, percentage of dark mornings are also linked to population size, as shown in the red first curve in the second chart. Here, high delays and high percentage of dark mornings are inimical to population growth. Comparing curves, at the lowest 3 k population trendline measurements, dark mornings go from 53% in the red curve to 17.5% in the green curve. In the real world, moves of this magnitude make a difference. Remedy resides in structure. The nation's counties are divided into halves. The prosperous counties tend to be larger than the 26 k midpoint. The remainder consists of many very small counties, half of all counties. Similar to trendlines shown in the first two curves, potential migration inclines leading to prosperity in high population counties deplete these already small counties. So far, we have been unintentionally locked into this approach, depleting the small to grow the large. To grow the small requires an entirely different tactic. The green curve contributes to fixing it. It massively reduces dark mornings for all counties. The fix flips the upward incline to a downward one. Its slightly downward incline gives an additional boost to low population counties. For all counties, it entirely removes direct or indirect unwholesome high-delay impact. It precisely shows population and percent of dark mornings conditions that exist at the instant we repair DST-TZ. The difference is immense. Flipping the incline grows, not drains, small counties. With the flip, all counties, this time including small ones, are better able to thrive and grow.
 

Best Cities Through Circadian Eyes

Livability.com has developed a list of the 100 best small to mid-sized US cities. Their analysis is confined to cities having median home values of $500,000 or less and populations between 75,000 and 500,000. Their emphasis is on quality of life and affordability. In particular, their highly discriminating process identifies exceptionally nice US cities, which, as we will see, have slightly lower delays and fewer dark mornings than the common case.
Morning sunlight in Top 100 US Cities
 Percentile:  2.5%  5.0%  10.0%  20.0%  30.0%  40.0%  50.0% 
 Median 		 60.0%  70.0%  80.0%  90.0%  95.0%  97.5% 
Delay
Top 50-14-13-9-30410.0132129344445
Top 100-16-14-13-6-1610.0142129364446
 Common Case 
Top 3000		-16-13-8-151118.0243035404447
Percentage of Dark Mornings
Top 509%21%25%28%31%34%41.0%46%49%57%60%66%67%
Top 1003%18%24%28%32%36%42.5%45%49%58%64%67%68%
Common Case
Top 3000		3%8%20%30%36%41%47.0%53%58%62%65%68%70%
Because they are decidedly more desirable than the average, these cities are excellent for analysis. We find that they, too, unwittingly benefit from lower delays and fewer dark mornings. At the Top 50 level, their median delay is 8 minutes less and their percentage of dark mornings is 6% lower than the common case. Just as in health rankings, lower delays and fewer dark mornings for cities tend to come hand in hand with superior performance. It is of interest that the counties in the prior Top 100 to 250 group have a segment 10-delay as do the 100 select cities here. The low delay and bright mornings may well have been contributing to these cities being attractive. From a circadian perspective with an eye to few dark mornings, the real estate mantra — "Location, Location, Location" — seems to carry additional weight. Perhaps this is not such a surprise. Again, looking at home values, we see values in this graph linked to delay and attending dark mornings. As delays increase home values decline. This suggests that characteristics of delay locations are directly or indirectly perceived and that subliminally low delay's desirable consequences are highly valued.
Home Values Decline When Delays Increase
RankMedian DelaySegmentMedian DelayRange Median Home Value
Top 508Top 508$1,512,200 to $829,600
Top 1007Top 50 to 1004$829,600 to $725,500
Top 2503Top 100 to 2501.5$725,500 to $568,500
Top 5007Top 250 to 50010$568,500 to $456,700
Top 7508Top 500 to 75010$456,700 to $392,100
Top 150010Top 750 to 150016$392,100 to $293,700
Top 300013Top 1500 to 300018$293,700 to $52,700
[Spreadsheet notes: Census, American Community Survey, B25077 Median Value. Ranked levels scaled to account for 835 data points.]
Home buying decisions and opinions about a city seem to be influenced by the mélange of circadian influenced components – home values declining as delay and dark mornings increase. For this reason, when measured by delay and percentage of dark mornings, the threshold of perception falls within a measurable range. In the first table in this section, it seems that we are able to perceive the difference between median 10-delay and 18-delay cities, as well as the difference between 41%-dark-morning and 47%-dark-morning cities. We call the former Best Cities and economists need to give them closer attention.
 

Property Crime, But Not Violent Crime, Linked to Delay

Delay seems to be moderately linked to property crime (R2=0.5044), but not to violent crime> (R2=0.0812). In the graph 1.00 represents the median rate of property crime. Other points on the y-axis represent deviations from it.
Delay & Property Crime [Spreadsheet notes: Get Delay by formula. Sort data on delay. Graph centered on rolling 56-point median, smoothed on 3-point centered moving average. Only 290 MSA data points readily available to public, in contrast to 3,000+ county-level FIPS points at CDC. This precludes detailed analysis. Data source: crime-in-the-u.s.-2019.]

Ultimately, as seen in the graph, high delays increase property crime; low delays reduce it. To reduce property crime there seems to be a payoff for driving delays south. On this trendline, going from the current average 16.9-delay to the normal average 8.2-delay appears to be a normal byproduct of the fix — seemingly a 3.5% reduction in property crime.

"Western Edge Effect" Meets the 2024 Election

The Western Edge Effect, measured here by "delay," impacts health and economics. This delay also appears to have influenced the 2024 election. The old saw, "Voting with your wallet," applied in the election. But that is not the main story. "Voting with your mood," is the main story. To win, Harris county vote ratios shown in these graphs would have needed to exceed one. (Vote ratio = Harris_vote/Trump_vote count.)

Harris Trump Vote Ratio and Income Graph

That story indirectly is evidenced by an astonishingly tight relationship between the Harris/Trump Vote Ratio and delay, as shown in the following graph and table. The table is sorted on the Harris/Trump vote ratio.

Harris Trump Vote Ratio and Delay Graph
RankMedian DelaySegmentHarris/Trump
Median Vote Ratio		PopulationAverage Per Capita
Personal Income		Median DelayMedian Current Dark
Mornings		After Fix
Top 508Top 503.38423,706,000$36,954838%23%
Top 1008Top 50 to 1002.17333,884,000$31,514839%23%
Top 2508Top 100 to 2501.50558,638,000$30,917938%22%
Top 5008Top 250 to 5001.02874,712,000$29,158940%24%
Top 7509Top 500 to 7500.74634,400,000$28,6251142%25%
Top 150013Top 750 to 15000.50855,747,000$27,4401747%27%
Top 300019Top 1500 to 30000.31493,388,000$26,0022352%28%
Ratio2.4
[Spreadsheet notes: Delay data from original computer program that developed the maps. Sort data on Harris_vote/Trump_vote Ratio. Graph centered on rolling 200-point median, smoothed on 30-point centered moving average. Note: Average income is about $450 more than median. Rank ratio 2.4 is equal to highest health ratio (obesity) shown earlier. For graphs in this section, population & income from pre-COVID, CDC Social Vulnerability Index 2018. Vote source: Dave Leip's Atlas of U.S. Presidential Elections, Preliminary data, downloaded 11/13/2024.]
Harris won roughly 400 of 3,000 counties. Wide median differences exist between Harris and Trump locations:
Harris8-delay, 36% dark mornings, $30,704 per capita income, and $5.6 trillion total personal income in 400 counties.
Trump 21-delay, 50% dark mornings, $25,941 per capita income, and $4.7 trillion total personal income in 2,600 counties. At a median 8-delay, Harris counties are characterized by being in sync. At a median 21-delay, Trump counties are characterized by being desynchronized. Harm seems to be created there. Being desynchronized, evidenced by high delays and a high percentage of dark mornings, typically produces adverse outcomes. In the table here, median segment delays of 17 and 23 at "Top 750 to 1500" and higher are especially harmful. The following three graphs answer the crucial question, "What are the average economic and election outcomes when given specific delays?" See the similarity of shape. Population and Total Personal Income patterns look much the same. The long-term player, in this instance, population, is author of the shape. As does circadian impact, it builds over many years. In all instances of existing conditions here there is a trendline decline from low delay to high delay. An entirely neglected voice, "delay," contributes at both ends of the curves. High on the left, low on the right.
Delay & Average Population Graphed Delay & Average Total Income Graphed [Spreadsheet notes: Get delay by formula. Sort data on delay. Graphs centered on rolling 200-point average, smoothed on 30-point centered moving average.]
In the above, the average delay in the Top 750 counties is a negative 5.8. With it come the nation's greatest success. In a polar opposite position, starting at a 33-delay, the bottom 750 counties (to the right of the improper time zone marker) come with an exceptionally high average delay of 40. With it we have the nation's weakest economic performance. Separately and in passing, it is interesting to note that traveling along the trendline in the Total-Personal-Income graph, going from the current average 16.9-delay to the normal average 8.2-delay might well have suggested, with the fix, over the very long term, as much as a 20% higher Total Personal Income per county.
Delay & Average Harris Trump Vote Ratio Graphed
The relationship between the Harris/Trump Vote Ratio and delay, i.e., sync, tells a great deal. The Harris/Trump Vote Ratio would have required a ratio greater than one for Harris to have a win. In the above, we see Harris's penetration is weak outside the 400-county Harris segment shown here [3-delay to 11-delay range, nationwide a median 8-delay]. To the right of the Harris Segment, at an 11-delay, the curve shows Harris support declining at increasingly high delays. By a 19-delay, in about half of all counties, the Harris/Trump ratio is typically 0.500 or lower, which is to say for every 5 Harris voters there are at least 10 Trump voters in these counties. By the low end of the trendline, it is closer to 4 Harris voters for 10 Trump voters. Here and elsewhere in this analysis, economic, health, social, and election decision-making appear to be influenced by delay — not by magic but, in part, seemingly via excessive dark mornings and subtle consequences of circadian influence. To the question: "Do CDC chronic health conditions and behavioral factors such as Obesity, Smoking, Depression, Leisure Time Physical Activity, Cognition, and Mental Health influence voting behavior?" a Google AI Overview responded:

Yes, CDC-related health conditions and behaviors like obesity, smoking, depression, and physical activity significantly influence voting, often showing that better health and engagement in healthy habits (like activity) correlate with higher voter turnout, while poor health, depression, and smoking are linked to lower participation, impacting who votes and potentially shifting policy focus, notes research from the American Heart Association.

Key Influences on Voting Behavior:

  • Obesity: Studies suggest links, with some finding higher conservative voting in areas with higher obesity rates, though the relationship is complex and varies.
     
  • Smoking: Daily smokers are significantly less likely to vote, potentially due to lower political trust, affecting public health policy outcomes.
     
  • Depression: Individuals with depressive symptoms have lower voting probabilities; the impact of mental health on participation is strong.
     
  • Physical Activity & Overall Health: Better physical health, more physical activity, and higher self-rated health are linked to higher voter turnout, while poor health reduces it.
     
  • Cognition: Health factors, including cognitive well-being, have a powerful effect on voting, similar to education levels.

Why the Connection?

  • Reduced Capacity: Physical or mental limitations can make getting to polls difficult.
     
  • Lower Civic Efficacy: Poor health might decrease trust in government or belief in one's ability to make a difference.
     
  • Health-Driven Priorities: Ill individuals might focus more on immediate health concerns than politics, or conversely, feel their health issues need political attention, influencing their vote.
     
  • Socioeconomic Factors: Health, education, income, and age are intertwined and all affect participation.

In essence, healthier individuals, especially those engaged in positive behaviors, tend to vote more, making health a significant predictor of political engagement, notes American Heart Association.

Outside the context of an election, low delays and few dark mornings are imperative. Otherwise, in many categories top performance is suppressed. The downward trendlines here and accompanying gloomy mornings lead to a bleak set of conditions. More positively, as shown in the above table's After Fix column, dark mornings can be easily limited to a safe, narrow band of median dark mornings lower than 28%.
 

DST Choices

Options Summary
DST options are effectively active for none, 1/3, 1/2, 2/3, or all of the year.
#1 No DST
Permanent Standard Time
#2 Memorial to Labor Day DST
May 20 - Sep 9, 113 Days, 31% of year
#3 1966 to 2006 DST
Apr 24 - Oct 30, 190 Days, 52% of year
#4 Current DST
Mar 10 - Nov 3, 239 Days, 65% of year
#5 Proposed Permanent DST
100% of year
DSTs were initially justified as wartime exigencies. In the US they have morphed into substantially a permanent creature. This is their background: Aiming to alleviate hardships due to wartime coal shortages and air-raid blackouts, on April 30, 1916 during World War I, Germany introduced the first DST. In response, twenty-one days later (May 21, 1916) the UK began its DST. Ten and a half months later (April 6, 1917), the US declared war on Germany. Eleven months later during WWI (March 19, 1918), the US employed its first DST, this time for seven months. During WWII, twenty-four years later (February 9, 1942 until September 30, 1945) the US again employed year-round DST (then called "War Time"), this time for three and a half years. An additional twenty-four years later (April 13, 1966), the US employed its first nationwide peacetime DST. Forty-one years later (March 11, 2007) the length of this DST was increased by seven weeks. Initially created as a war exigency, we since have had nationwide, peacetime DSTs for 60 years. These have not been structured to meet current peacetime needs.
 

What About the Press? Improper Time Zones vs. DST

Via excessively long DSTs, 280 million people in the US are desynchronized for nearly eight months of the year. Via improper time zones, fifty-three million people are desynchronized for 100% of the year. While DST gets the press and public attention, these fifty-three million Americans in 900 counties are often ignored. Time zones are assumed to be a sleeper story. Not so. The story is a lot bigger and more important than just: "For it" … "Agin it."
Median Number of Dark Mornings
Before Time-zone FixAfter FixRatio: Before Time-Zone Fix/After Fix
Permanent Standard Time99691.43
Current DST1721131.52
Ratio: Before DST Fix/After Fix1.741.64Simultaneously fixing both: 2.5
A Room Full of Elephants. There is only a slight difference between exclusively repairing time zones and exclusively eliminating long DSTs. Attending to DST alone leaves almost half the job undone. As measured by changes in number of dark mornings, eliminating long DSTs has only a 14% advantage over repairing time zones [=1.74/1.52]. Repairing both together has a 2.5x advantage [=172/69]. As to the impact of time zones, by virtue of their 365-day length, they keep us desynchronized 1.5x longer than the current DST [=365/239]. And then there is the question of choosing a DST length, a topic on which surprisingly no ink is spilled. Regional considerations also come into play. In the dead of winter, an inappropriate time zone increases winter morning coldness. Since the current DST is inactive during these coldest days of winter, it does not. For this reason, greatest payoff in northern regions often comes from fixing an inappropriate time zone. By a large margin, as measured by minutes of delay, the current DST and inappropriate time zones have put us out of sync with time. However you choose to make comparisons, the impacts are gargantuan, involving many millions of people. The misalignment is unnecessary.
 

Fixing It

Most countries don’t observe daylight saving time. DST fix: Arizona and Hawaii have rejected Daylight Saving Time. Without congressional action, 15 U.S. Code § 260a allows any state to go on Permanent Standard Time within its borders. Conversely, to change a DST requires congressional action. Thus, to choose a short Memorial to Labor Day DST would require congressional action. In most cases, these two options yield about the same percentage of sunrises after 7:00 AM. Scholarly studies have not addressed attributes of a short Memorial to Labor Day DST.
Wikipedia indicates that:
Permanent Standard Time is considered by circadian health researchers and safety experts worldwide to be the best option for health, safety, schools, and economy, including the American Academy of Sleep Medicine, National Sleep Foundation, American College of Chest Physicians, National Safety Council, American College of Occupational and Environmental Medicine, Canadian Sleep Society, World Sleep Society, Society for Research on Biological Rhythms, and several state sleep societies. Permanent Standard Time is supported by advocates for school children, including the National PTA, National Education Association, American Federation of Teachers, National School Boards Association, and Start School Later. They cite both the health benefits of circadian alignment, and the safety advantages regarding morning commutes.
Time Zone fix: The old bedrocks on which US time stands (to "promote the adoption and observance of uniform time within the standard time zones"; 1918, 1919, 1966), now 58 to 106 years old, have not delivered an orderly or uniform time. What they have delivered is a massively adulterated time. Time zones are defined at county levels named in the map tables. There are two ways an area can be moved from one time zone to another: by Federal statute or by Secretary of Transportation regulation. The dark red regions in the first map have long delays caused by ancient time-zone choices for western-edge counties. Changing time zones that now apply would place these counties in an enviable position — a move from the darkest first map color to the lightest, a 60-minute reduction in delay. Quick Local fix: For DST rejectionists, experiments to maintain sync with solar time at home by setting sundials, clocks, smartphone apps, and watches to local solar time and using DST time elsewhere are occasionally possible. When stuck in untenable circumstances, this option can be useful, if not pleasant. With all the gadgets of modern life the lowly sundial, set to local solar time, provides a nice connection with a higher authority. The honest sun. When its shadow strikes 12, we have an apt reminder that half the day is done and another half awaits us. This, punctuated with lunch at solar noon, provides a reliable regularity, a perceived as well as an unconscious orderliness as the day unfolds. Sundial Sync by lamp timer Google_Clock With a retro flavor, bedside & table lamps and mechanical timers can provide a consistent, unobtrusive year-round assist for maintaining sync. [Warm 4 watt incandescent, candelabra E12 bulb for dim light, 7 watt for brighter light, or 7.5 watt incandescent for conventional E26 socket.] This can provide sufficient cues to nudge us into an appropriate, year-long mealtime and sleep routine. Begin meal when light turns on. Head to bed when light turns off at night. The evening light-on period provides warm, dim lighting in preparation for sleep and does double duty as a night light. A long wait between last meal of the day and bedtime is often recommended. Timer set to turn on: 1) for the appropriate lunch hour, and 2) during the dinner-to-bedtime period. Or, with a Pavlovian touch, an app like Google's Clock can prompt: Wake up, Lunch, Dinner, and Bedtime.
 

Bedtime for Night Owl??

A Google AI overview of Night Owls reads:
" 'Lark' and 'owl' are terms used to describe people's chronotypes, or their typical bedtime and wake-up times. Larks are people who go to bed before 11 PM and wake up before 8 AM, while owls are people who go to bed at or after 11 PM and wake up at or after 8 AM. …"
Bedtime & Night Owl
Proper
Standard Time		DST TimeDST Plus Improper
Time Zone
8:00 PM9:00 PM10:00 PM
8:30 PM9:30 PM10:30 PM
9:00 PM10:00 PM11:00 PM
9:30 PM10:30 PM11:30 PM
10:00 PM11:00 PM12:00 AM
10:30 PM11:30 PM12:30 AM
11:00 PM12:00 AM1:00 AM
11:30 PM12:30 AM1:30 AM
12:00 AM1:00 AM2:00 AM
Now, let's consider your preferred time to go to bed in a world in which there is no DST-TZ. Let's say in this hypothetically pure world, your preferred time for shut-eye is an unadulterated proper time of 10:30 PM. If these circumstances are seen from a DST perspective, your preferred bedtime instead would appear to be 11:30 PM, a Night Owl. From a perspective of DST combined with an improper time zone, your preferred bedtime would appear to be even later, 12:30 AM, again a Night Owl. Your modest and sensible intention of simply choosing a proper 10:30 PM bedtime calls you a Night Owl in either of these two cases. The term Night Owl may be saying something about social time, but it is on less firm ground when it comes to fundamental conditions. We are separated from the natural unfolding of the day to the extent that often we cannot recognize its underlying time. Layers of adulteration have created a fictitious time, a time distorted to such an extent that not only new seasons of winter morning darkness have been created, but even ordinary events, such as identifying bedtime, have become needlessly confusing, often misleading. As a ChatGPT conversation observed: Many “night owls” are made, not born. In western parts of time zones, populations systematically appear “later” — not because of personality, but because morning light arrives late by the clock. Labeling this as “night owl behavior,” pathologizes normal biology, normalizes structural delay, and masks the role of geography and policy.

The Claim That DST Promotes Physical Activity Is Weak

A Google AI Overview Indicates: Evidence suggests that the claim that Daylight Saving Time (DST) promotes increased physical activity is weak, with studies indicating that, rather than boosting overall activity levels, DST primarily shifts existing activity from mornings to evenings. Research shows no significant increase in total daily physical activity and, in some cases, a decline in gym visits and an increase in sedentary behavior. Key findings regarding the weak connection between DST and increased physical activity include: Therefore, the assumption that more evening light automatically results in a more active lifestyle is not strongly supported by research, which often highlights a, at best, marginal effect on activity levels.
 

The Choice Facing Us

Question: In terms of health and practicality of implementation, how should we evaluate the following three DST options? Google AI Overview’s Response: The evaluation of Daylight Saving Time (DST) options depends on the tension between circadian biology (health) and economic/social convenience (practicality).
1. Current DST (March to November)
  • Health: Poor. The "Spring Forward" transition is linked to immediate spikes in heart attacks, strokes, and traffic accidents. The extended duration (8 months) causes chronic sleep deprivation for many by delaying the body's release of melatonin.
  • Practicality: Moderate. While it is the status quo, the biannual clock change is increasingly unpopular and costly due to lost productivity and scheduling errors.
2. Permanent Standard Time
  • Health: Optimal. Medical organizations (e.g., American Academy of Sleep Medicine) favor this. It aligns the social clock with the solar clock, where solar noon is closest to 12:00. This promotes better sleep quality and metabolic health.
  • Practicality: High. It eliminates the biannual shift. However, it is often resisted by the retail and tourism industries because of the loss of one hour of evening daylight in the summer.
3. Permanent DST
  • Health: Worst. It forces the body to stay out of sync with the sun year-round. In winter, many would commute and start school hours before sunrise, which is linked to seasonal affective disorder and cognitive impairment.
  • Practicality: High. It eliminates clock changes and is popular for evening leisure. Historically, however, it fails; the U.S. tried this in 1974 but reverted within months due to public outcry over dark winter mornings.
Often it is Permanent DST that promises, but it is Permanent Standard Time that brings home the bacon. By repeating the urban legend that DST benefits them, retail and tourism industries wrongly oppose permanent standard time. Take note. In complete reversal to their expectations, the fewer dark mornings that come with Permanent Standard Time greatly benefit their industries! Although DST promises “more evening sunshine and more physical activity,” sleep debt and fatigue created by DST undermines the very energy people need to enjoy additional evening sunlight (see graph, see DST produces a surge in inactivity, and see sedentary activity increase). In contrast to pro-DST beliefs, permanent standard time's few dark mornings reliably deliver increased leisure-time physical activity, as again shown in the graph.

How long is it going to take to get Permanent Standard Time?
This is the up-count since
Year 0 Days 0

The Question: ”Long and short term: What is the chance of implementing permanent standard time in the United States?” Google's AI Overview Response: The chance of implementing permanent standard time (pST) in the United States is currently low in the short term, despite having high support from medical experts and a plurality of the public. While there is strong, bipartisan consensus on ending the twice-yearly time change, Congress has stalled on whether to make daylight saving time (DST) or standard time permanent, with recent, 2025-2026 efforts heavily focused on the former. Here is a detailed breakdown: Short-Term (1–2 Years): Low Likelihood Long-Term (3+ Years): Moderate Likelihood Summary of Options Ultimately, while there is a strong, growing movement to end the clock change, the specific implementation of permanent Standard time faces political competition from the push for permanent Daylight Saving time.

Who Promotes Permanent Standard Time?

The question: “Who promotes Permanent Standard Time?” Google’s AI Overview response: Permanent Standard Time (PST) is primarily promoted by sleep scientists, medical associations, and safety experts, including the American Academy of Sleep Medicine (AASM), the American Medical Association (AMA), and the National Sleep Foundation. They advocate for a year-round "natural" clock to align with human circadian biology, improving health, safety, and productivity, as opposed to Permanent Daylight Saving Time. Key organizations and groups advocating for Permanent Standard Time include:
  • Medical & Scientific Organizations: The American Academy of Sleep Medicine (AASM), American Medical Association (AMA), World Sleep Society, National Sleep Foundation, and the Society for Research on Biological Rhythms.
  • Advocacy Groups: The Coalition for Permanent Standard Time (CpST), which includes groups like the National PTA and National Safety Council, and Save Standard Time.
  • Key Arguments: Proponents argue that standard time reduces risks to physical/mental health, improves morning commute safety, and aligns better with the sun’s position compared to Daylight Saving Time.
These groups often oppose the "Sunshine Protection Act" which proposes permanent daylight saving time, arguing instead for the year-round, non-shifted standard time.
An aside: Given their widespread harm, eliminating DST and inappropriate Time Zones merits wider support.

Urgent Need for Study
So Far, Excessive Silence from Academic and Popular Press
& Fitness Device Manufacturers

When prompted by an ordinary Google search, "Percentage of dark mornings circadian impact on chronic diseases," a Google AI Overview responded: "While research broadly confirms that circadian disruption (such as insufficient morning light exposure and night shift work) significantly increases the risk of various chronic diseases, the available studies do not quantify the impact of "dark mornings" as a universal, single percentage across the population and different diseases. … " To repeat: 'Available studies' do not address the impact of 'dark mornings' across the population and different diseases. This, notwithstanding that the CDC Places database, in a FIPS specific fashion, provides sufficient data to evaluate all major chronic disease categories for each of 3,000 counties in the continental United States. And, NOAA also provides exact sunrise times for each location. Excel DM spreadsheet v2.0 also contains, at a FIPS specific level, exact delays and trendline percentages of dark mornings for all counties in the continental United States. The main ingredients are available and well known. For sixty years, we have sleepwalked into DSTs and corrupted time zones that have augmented chronic diseases and harmed our economy. Until available studies, in the academic and popular press, quantify the impact of percentage of 'dark mornings,' we can continue in ambiguity and inaction. In which case, circadian-related public health will suffer — perhaps again for the next sixty years.
Instead:
  Health and performance better when DST forever ends Focused circadian public-health

 

Conclusion: New Seasons of Winter Morning Darkness, A Summary of Options

Long DSTs and inappropriate time zones have artificially created seasons of early morning darkness that would not normally exist. Correcting this, the DST-TZ fix puts an absolute cap on morning darkness. No county whatsoever experiences more than 37% of sunrises after 7:00 AM. This is fundamentally different from the current DST, which, at the median, can barely limit late sunrises to 47% of the year. A yawningly wide gap exists between the currently practiced DST & time zones and the fix. In this graph we see that with the fix, 90% of counties would be in the highly desirable position of having 30% or fewer dark mornings. You could hardly wish for better than this.
Winter_Darkness_Current_vs_Fix

Percent, Days, and Months of Sunrises Later Than 7:00 AM. Before and After Repairing Time Zones.
 
Before Repairing Time Zones
EventMedian PercentDaysMonthsRatioMax PercentDaysMonthsRatio
 Permanent Standard Time 27%993.21.446%1685.51.2
 Memorial to Labor Day DST 28%1023.41.562%2267.41.7
1966 to 2006 DST39%1424.72.179%2889.52.1
Current DST47%1725.62.588%32110.62.4
Permanent DST54%1976.52.888%32110.62.4
After Repairing Time Zones
 Permanent Standard Time 19%692.31.037%1354.41.0
Memorial to Labor Day DST19%692.31.037%1354.41.0
1966 to 2006 DST26%953.11.449%1795.91.3
Current DST31%1133.71.659%2157.11.6
Permanent DST46%1685.52.468%2488.21.8

[Spreadsheet notes: Excel percentile formula used to produce graph. Data comes directly from original NOAA-based computer program.]
At the median with the fix, the table shows that we have only 69 days of sunrises after 7:00 AM. We are physiologically well adapted for a 69-day season of morning darkness (19% of mornings dark). It is identical to conditions that existed before DST was invented. The fix is no more than the return to substantially normal time. The vastly longer dark seasons now imposed on us are unnecessary. The current DST and its accompanying time zones, with its median 172 days of morning darkness, are pointless and harmful. The current dark mornings create burdens 2.5x greater than we would normally experience. Especially for schools, they have created school bus and cognitive problems that can be fixed only by a change in DST and accompanying time zones. For the rest of us, they are harming our economy, our income, our home values, and our health. The time for acting has long since passed. At Federal, State, and local levels we must effectively address: The current DST and corrupted time zones are sham treatments. They require scrutiny. Then abandonment.

Abolish DST

Daylight Saving Time Is the Worst
Daylight Saving Is a Trap
More Than Half in U.S. Want Daylight Saving Time Sunsetted
Daylight saving time causes lower productivity and higher healthcare costs
Most countries don’t observe daylight saving time
Google Scholar: Medical Group Position Statements on Daylight Saving Time
Save Standard Time
Google Scholar: Topic, Adverse DST Effects For Adolescents
Kids on way to school endangered by morning darkness
School Bus Stops: Waiting in the Dark
DST Analysis
Why daylight saving time may be bad for your brain and health Headwinds now in precisely the opposite direction. Senate (S.582), Congress (H.R.139), and Executive branch pressing to make daylight saving time the new, permanent time in the United States.
April 2025, Senate testimony was received from Neurologist Karin Johnson and golfing representative, Jay Karen.

Health Links

Why dark nights and bright days are good for health
How permanent standard time could save lives, explained by a sleep expert
How daylight saving time poses a host of health concerns, according to a neurologist
Daylight Saving Time and Your Health Plus, Steps to Saving Zzz's
Breast cancer risk higher in western parts of time zones

DST Interactive Maps in the News

NewsNet: Interactive Maps Put a New Perspective on Daylight Savings Time
New York Tech: Five DST Looks To Reimagine Our Clock-Changing Habits
Digital Journal: Surprise in Cheboygan, a DST that Increases Morning Sunlight
Andy Woodruff: Where to hate daylight saving time and where to love it
Bloomberg: Where Mornings Would Get Darker Under Permanent Daylight Saving Time
Washington Post: Brighter winter evenings would come at the expense of darker mornings.

Download excel spreadsheet for delays and percentage of dark mornings for all counties in the continental United States
Download NOAA Sunrise.xls Spreadsheet
With cartography, programming, publicly available databases, techniques mentioned in spreadsheet notes and links, the above was created. It is intended to contribute to the discussion. Do not construe any of this as medical advice. For that, consult a healthcare professional. I am not a healthcare professional.
Creative commons license CC BY. Courtesy of Ike Jeanes. Developed by DSTmap.com.