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Let’s Turn Off Daylight Saving Time

The spring-forward fall-back changes cost businesses money, and the promised energy savings have never materialized. Pro or con?

Pro: A False Economy

Although Daylight Saving Time (DST) has been justified as an energy-conservation measure, it is no such thing.

Studies conducted by University of California researchers on Indiana before 2006, when the state operated under three different time regimes, and on Sydney, Australia, which extended DST to accommodate the 2000 Summer Olympic Games, show either no difference in energy consumption or a small increase in power usage during the months immediately after clocks were moved an hour ahead.

While these studies call into question the promised energy savings, there is no doubt about the costs of DST. According to my back-of-the-envelope calculation, in the U.S. we divert nearly $1.7 billion worth of valuable time to the annual spring-forward, fall-back exercise. That’s the opportunity cost—time that could be better spent on more productive things.

Economists typically value the opportunity cost at an individual’s wage rate. The Bureau of Labor Statistics preliminarily estimates that the average American’s hourly wage was $22.45 in January 2010.

Assuming it takes everyone 10 minutes to change all of his or her clocks and watches, the opportunity cost equals $3.74 per person. The one-time opportunity cost for the nation (based on total U.S. population over 18 years old, excluding residents of Arizona, which doesn’t observe DST) therefore is $836,117,536. Since clocks are changed twice yearly, the total must be doubled.

Businesses feel the costs as well. More than 1.5 billion people globally need to adjust clocks and schedules, even if their own countries haven’t officially adopted DST.

There are no real benefits and some very real costs related to DST. Congress should repeal the tyranny of government time and leave our clocks alone.

Con: Proven Benefits

Instead of turning Daylight Saving Time (DST) off, Congress should turn it on year-round.

First, despite the contrarians, DST saves energy. Why? Far more oil, electricity, and energy are used during evening darkness than morning because more Americans are awake at 5 p.m. than at 6 a.m. Hence, shifting sunlight to the evening causes a significant reduction in evening peak load, which outweighs a small increase in the early morning load caused by DST.

There are many more important advantages to DST. Numerous types of crime, including assault and theft, peak during evening darkness, while the corresponding rates are very low during early morning. Happily, DST allows society to take advantage of the fact that criminals are late to rise and late to bed.

The crime reduction associated with prolonged daylight helps individuals and businesses alike. U.S. retailers lost $42.2 billion to theft from mid-2008 to mid-2009, according to the Global Retail Theft Barometer, so a reduction in theft could mean big savings. The impact would be felt by mom-and-pop and big-box stores alike because 92% of retailers were theft victims in 2009, the National Retail Federation reports.

Most important, however, is the fact that DST saves lives. Simply put, darkness kills. Extending DST year-round would save more than 350 American lives annually in reduced traffic fatalities during the evening. According to the Insurance Institute for Highway Safety, the change from daylight to twilight causes a 300% increase in fatal pedestrian crashes alone. Having this change occur one hour later saves lives because fewer motorists are on the road then.

The advantages of year-round DST—including energy conservation, crime reduction, and lives saved—clearly outweigh the disadvantages. It is past time for us to shift our thinking permanently forward on DST.

Opinions and conclusions expressed in the Bloomberg BusinessWeek Debate Room do not necessarily reflect the views of Bloomberg BusinessWeek,, or Bloomberg LP.

Reader Comments


I agree to both.


This opportunity cost argument seems hollow. Ten minutes to change clocks at 2 am in morning? Not all work in night shifts. The claim for no reduction in energy consumption is not buttressed by facts.


The opportunity cost seems hollow because in this era many clocks are synchronized through the Internet or radio to automatically adjust themselves. When was the last time you changed a computer or cell phone clock for DST?


The latest DST schedule in the United States put us out of synch with DST schedules in Europe and other overseas air destinations. This complicates international flight schedules during the overlap periods. If we are to have DST at all, it is better that it be during the same time periods worldwide. Better still we could just eliminate DST alltogether. As a native American once said, you cannot make a blanket any longer by cutting a piece off one end and sewing it on the other.



I think you may have just nailed it!


Instead of adjusting the time, you can derive the indicated "benefits" by changing the schedule to match the daylight. This is practiced in many countries.

David Eng

I really don't get the idea of DST--why don't we just have "winter" time all year round? Perhaps someone can explain this to me. First, winter has the shortest daylight available. Sun rises at 7 am and sets at 5 pm. During summer, the sun comes out earlier (say 5 am) and sets later (say 8 pm). By keeping the "winter" time all year round, you get additional sunlight whether it is early in the morning or late in the evening for summer. Now that we have planned for the worst case scenario in winter, why do we need to adjust the time for summer, which has more daylight?

oldy moldy

I love DST and wish it would stay year round. I do not like to drive or be out and about after dark and DLT allows me a lot more freedom. I know it still stays lighter longer in the summer, but I still really, really appreciate that extra hour. The younger people just don't understand the tremendous benefits of DST for those of us who are older and don't see as well or feel as safe out there at night. Please don't try to cancel DST on us. I want it year round if that's ever possible. There wouldn't be a lost hour of sleep if they'd just keep DST year round.

Alex R

Let's stop making unnecessary changes. Summer time shift adds 1 hour of light every day, which is a great thing if you fly aircraft or ski or hike or work outside. Not a problem to change your clock twice a year, in exchange for the extra daytime hour.

You can't make all time 'DST' because then you will wake up in the darkness in the winter.

So can we stop speculations and start to think about real problems?


I agree, with all the modern machinery in the ag sector, DST does not have the same results in what was meant for it when it first took effect.

"Trash it."

The cows don't know the differance anyhow.


The problem with changing the schedule to match the daylight is that humans are creatures of habit, and we synchronize our routine activities (getting up, eating lunch, etc.) to wall clock time.

If gleaning that extra hour of early evening daylight in the summer meant that businesses had to shift their business hours forward (e.g., be open from 8-4 instead of 9-5), it would simply never happen, because all the changes required (e.g., changing time cards) would be far more invasive than just changing the clocks in the first place.


The problem is jerking our sleep rhythms around. It takes weeks to get back into a rhythm. But it really screws up teenagers that have to get up before light to go to school.

Good sleep is crucial to good health and this going back and forth causes health problems. Sleep deprivation is also important for brainwashing people, hmmm.

Stephen Scott

Although I lean to the "con" argument on economic costs and benefits, I am prepared to accept that neither case is made conclusively here. But I live in Montreal, Que., and in winter it is pitch black outdoors before 5 P.M. Daylight Savings Time comes each year as liberating-- a great morale boost. We can debate the pros and cons. But what is this about the "tyranny of government time"? I read Mr. Shugart's argument with interest. But is it necessary for him to employ "hype" and overstatement? Cannot public affairs be discussed with a balance and restraint? Time, as shown on clocks,even standard time, is the creature of government--of individual governmnets and of intergovernmental agreements. With the advent of the railway it became clear that no scheduling and no traffic management on a transportation system could exist withot standardization of time. Some readers might care to read the biography of Sir Sandford Fleming on Wikipedia.

Harry Tuttle

You "Con" guys are joking right? I mean, I'm sorry to be so out-of-touch, but I'm going to answer as if you are serious.

Why would you make the change all year long? You (and businesses) have the choice to simply get up an hour earlier or later. What are you, sheep? How about taking the initiative in your own life and make an intelligent decision for yourself?

One more thing. I still know many people whose electronic calendars are out of whack since the 2007 DST change. It seems a little silly to have IT departments out spending resources on this garbage.

The whole DST issue is very symbolic of how some humans seek to shift reality--in this case, the flow of time--to meet with their desires, instead of making simple behavioral changes. DST embarrasses me as a human.


Sorry, but DST is foolish, and the con argument does not hold water. Fact: The days are longer during summer hours. Thus, any perceived "savings" that are argued in the con argument are a result of longer daylight hours, not playing with clocks.

People go to work and come home from work at all hours of the day, and a government plan to change clocks doesn't change that, nor does it fool the sun. So I now have to turn on the lights in the morning for an extra hour instead of at night. Only Arizona has a legislature that understands the basic tenant that only a fool can cut a foot off of the top of a blanket, sew it onto the bottom, and think that he now has a longer blanket. Well, apparently according by the con argument and several of the posts here, this "logic" extends beyond elected officials.


Ben Franklin was the 1st proponent of DST. In his day, the vast majority of Americans were farmers and there was virtually no artificial light, so sunset put an end to nearly all human activity. So DST made at least some sense then.

However, this is not the 17th century. Artificial light is plentiful (ask any astronaut) and we now live in an industrial society with shift work and many night activities. Also, we now have vast networks of servers and other computers running 24/7. So what little energy might be saved in the early evening is negated in the early morning.

Calandrillo is also lying about traffic safety. Pre-dawn and dusk are the most dangerous driving hours, and DST puts the morning commute into pre-dawn. Every year many children are killed or injured in March, October, and November walking to school or waiting for buses in DST-induced morning darkness.

As for crime, the answer is to crush the criminal element without mercy or regret, not adjust to it or appease it with clock-tinkering.

Perhaps Mr. Calandrillo's thinking is affected by living in Seattle, where sunrise in midsummer is around 5:15 PDT. Year-round DST would move Seattle sunrise at midwinter to nearly 9:00. Apparently Mr. Calandrillo is one of those wealthy elites who can get up when he feels like it; the rest of us have to rise at or before 6 a.m., when thanks to DST it's still dark even at midsummer here in "flyover country." Down south there is less summer daylight, which is another reason Hawaii, like Arizona, does not observe DST.


I can make better recreational use of an extra hour of evening light, but Strider is right, you aren't gaining any daylight in this trade and where you make the evenings safer you make the morning commute more dangerous. The entire pro arguement seemed quite poorly thought out. I do, however, still like the extra hour at night.


I say leave one way or the other, I don't care which one. It's the changing it again and again that I hate. It may only be one hour, but it's very hard to adjust, especially for families with young kids. If DST is better, just leave it year round!


I can't wait for DST each year for better quality of life. It was a great feeling to come home from work to sunshine at 6:15 last night and go out and play catch with my son Without DST, its about another month of darkness and twilight.


As far as the clock changing, it is true that most computers can change the time on their own but many pre DST2007 devices have to be changed 4 times a year due to the old programmed DST on which they change and then again on the new DST.

If the government wants to control time, then they should invest in a far better Radio Frequency National Timeclock. I know I have several so-called atomic clocks and at my location none of the devices auto set.

Our current DST program is just a "Rob Peter to pay Paul" concept and if they really want to clean this up then split the difference in time and stop the current DST program.

Anton Shahu

I don't care about energy savings but rather of my time: My family and I have better use of daylight during summer.

My proposal: Don't keep changing it every couple of years. The confusion and lost opportunity "cost" of switching the clocks and synchronizing meetings stems from the fact that it keeps changing and it's different with Europe.

If people understand 29 days of Feb in a leap year so can they understand DST.


After giving this issue some thought, I have a theory. DST sucks if you have to be up early, usually for a job or school. Not only is it dark in the morning, it is hard to sleep because people stay up making noise. If you are up later in the day, DST is great.

Some people claim that DST in necessary because it makes adjusting schedules easier. The fact is, many businesses have different summer and winter hours even with DST. For example, if a restaurant closes at 10:00 pm during the winter, they might need to stay open until midnight during the summer.


Strider's comments are correct.

DST was introduced primarily to assist farmers, back when fifty or sixty percent of our population lived on farms, and there were chores that had to be done before going off to school. (This is alone why schools close for ten weeks each summer; the kids were needed to help with the farm work.) Now that perhaps only two percent of our families operate farms, automation has replaced much of the manual labor, electric lights have replaced oil lamps, and almost no child walks to school any more, perhaps it is time to consider whether DST is an anachronism we can do without.

Or we could do what the military world wide is doing more and more of: schedule everything by Zulu time (Greenwich mean time). -just kidding- sort of.... -but then again....?


I want you to stop daylight saving time because my physical condition worsens.


Strider, you are wrong. Benjamin Franklin was not the 1st proponent of DST (as we know it). During his time as an American envoy to France, Benjamin Franklin, author of the proverb, "Early to bed, and early to rise, makes a man healthy, wealthy, and wise", anonymously published a letter suggesting that Parisians economize on candles by rising earlier to use morning sunlight.

Modern DST was first proposed in 1895 by George Vernon Hudson.
Either eliminate DST or go permanently DST. I don't care. Just quit changing the clocks. It makes no sense to do that any longer.

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