Clocks determine so much of daily life. Businesses open at the same time every day, schools start at the same time every day, we commute to work at the same time every day, and we leave work at the same time every day. All of this sounds perfectly reasonable for an industrialized society and it certainly works. While we may complain about having to get up and go to work, having an early morning doctor’s appointment, and not having time to complete our “to do” lists, we live by a schedule that is time-based. People often comment when they retire that they are no longer on a schedule. For most people this is a new and unfamiliar experience. They wake not to the annoying beep, beep, beep of an alarm, but to the sun.
Given that Western society relies on the time of day, and not the exact position of the sun, why do we need Daylight Saving Time (DST)? Why do we need to set our clocks ahead in the spring and back one hour in the fall? Conventional wisdom says that it was farmers who lobbied for an extra hour of daylight in the summer months to work in the fields. Contrary to popular belief, American farmers did not favor daylight saving time; the agriculture industry was deeply opposed to the time switch when it was first implemented as a wartime measure in the United States in 1918. The sun, not the clock, dictates farmers’ schedules, so daylight saving time was very disruptive. Farmers had to wait an extra hour for dew to evaporate to harvest hay. Less could be accomplished in a day because farm workers relied on the clock to start and end their work day. Nor were cows ready to be milked an hour earlier in order to meet shipping schedules. Agrarian interests led the fight for the 1919 repeal of national daylight saving time, which passed after Congress voted to override President Woodrow Wilson’s veto.
So who came up with the idea? New Zealand entomologist, George Vernon Hudson, and English builder, William Willett independently conceived of the idea of DST in the late 19th century. Their rationale was similar: each wanted to advance the clock during summer hours, not for economic reasons, but for personal pleasure. Hudson wanted additional daylight after he got off work to pursue his avocation of collecting insects. Willett wanted extended afternoon sunlight to allow him to play a complete round of golf after work. DST has been adopted and abandoned at various times since its inception in different countries, but became widely adopted in North American and Europe as a result of the energy crisis in the 1970s.
It was argued that DST would reduce the consumption of electricity, particularly for lighting in the summer months. While this contention has been called into question, it is still heard whenever the issue of DST comes up in Congress. In 2002, Rep. Julia Carson (Indiana) advanced the traditional political reasons favoring DST.
“Daylight saving time will save Indiana families over $7 million annually in electricity rates alone. It will give a windfall to small and large businesses alike by lifting barriers to competition, improving communication and commerce, and saving millions on improved energy efficiency statewide. For our communities, this will be one more step in preserving our cherished way of life by perfecting our health and safety. By all of Indiana observing daylight saving time, toxic emissions would be reduced by more than 240 million pounds annually. With more daylight, schoolchildren will not have to travel to and from school in the dark. For families, there will be more time for outdoor leisure and recreation after the work day is over. All of this is by simply changing our clocks just twice a year.”
This same line of reasoning held in 2007 when Congress voted to extend DST from the second Sunday in March to the to the first Sunday in November. Commenting on the Energy Policy Act of 2005, Rep. Todd Tiahrt noted
“Another conservation provision in the energy bill is the 4-week extension of Daylight Savings (sic) Time. By simply extending Daylight Savings (sic) Time 3 weeks in the spring and 1 week in the fall, we will reduce energy consumption equal to about 100,000 barrels of oil per day for four weeks. This energy saving time provision will also contribute to lower crime and fewer traffic fatalities.”
Politicians have used the energy argument repeatedly to demonstrate the utility of DST. Unfortunately, scientific data simply do not support this contention. A U.S. Department of Transportation study in the 1970s concluded that total electricity savings associated with daylight saving time amounted to about 1 percent in the spring and fall months. However, as air conditioning has become more widespread, recent studies have found that cost savings on lighting are more than offset by greater cooling expenses. Studies of the economics of DST have focused primarily on residential energy and have generated mixed results. A 2008 study examined billing data in Indiana before and after it adopted DST in 2006, and concluded that DST actually increased overall residential electricity consumption by 1% to 4%, due mostly to extra afternoon cooling and extra morning heating; with main increases coming in the fall. The overall annual cost of DST to Indiana households was estimated to be $9 million, with an additional $1.7–5.5 million for social costs due to increased pollution . A 2007 study found that the extension of DST for an additional month had no effect on electricity consumption in California . The Department of Energy reviewed the impact of the extension of DST by additional month, and concluded that, at best, electricity consumption was reduced by 0.5 % each of the days of the extension. That means a maximum savings of 0.03% over the entire year. The report also concluded that the savings were not uniform across all states, with the South experiencing savings due to increased household air conditioning usage .
Moreover, there are substantial costs associated with DST that are conveniently overlooked by politicians. For example, DST significantly affects stock market trading [6, 7]. On the Mondays after the Fall and Spring time changes, the NYSE, AMEX, and NASDAQ exchanges experience a one-day loss of $31B. This is attributed to the effects of a disruption in the sleep patterns of investors as well as brokers. The spring shift to daylight savings time, and the concomitant loss of one hour of sleep, resulted in an average increase in traffic accidents of approximately 8 percent, whereas the fall shift resulted in a decrease in accidents of approximately the same magnitude immediately after the time shift .
Workplace injuries among miners increased 67% on the Monday after the shift to DST in the Spring . Reduced productivity (cyberloafing) was found to increase significantly as well after the shift . As troubling as the foregoing results are, a significant reduction in SAT scores has been found as a consequence of DST among Indiana high school students . A recent study suggests that the cost of DST in the U.S. alone in terms of the health effects and lost productivity is well over $400M per year .
Let’s face it, we must sleep to survive. Like food, water, and shelter, sleep is essential for all mammals. The CIA and other government agencies have found that one of the most successful interrogation techniques is sleep deprivation and it has the added benefit of not being considered torture under US law. Sleep is necessary to normal physiological processes and has a distinguished evolutionary history. By legislating sleep deprivation, we are trying to overcome our evolutionary history. Failure to recognize this obvious fact, leads to all sorts of problems.
So why do we persist in observing DST? It is about money. Since 1915, the principal supporter of daylight saving in the United States has been the Chamber of Commerce . Retailers and outdoor sports activities benefit significantly. The primary movers in the daylight saving movement are the golf and candy industries. The golf industry is said to have benefited by an additional $200 million in additional sales of golf clubs and greens fees, just from adding one additional month to DST; and the barbecue industry is said to have sold an additional $100 million in barbecues and charcoal briquettes. The extension of DST in 2007 into November was strongly supported by the candy industry, which sells a lot more Halloween candy when kids can spend an extra hour trick or treating before bedtime.
Once again, we find that it is not common sense, rational thinking, or scientific data, but money that imposes DST on the US. Politicians rely on contributions from businesses to get reelected. While vigorously denying the influence of lobbyists on particular pieces of legislation, it is clear that special favors are accorded to political contributors. There is no rational basis for DST in the 21st century, save for a political system that is firmly based on money.
- Representative Julia Carson (IN), Daylight saving time. Congressional Record, 2002. 148(H1191).
- Representative Todd Tiahrt (KS), Conference Report on H.R. 6, Energy Policy Act of 2005. Congressional Record, 2005. 151(E1736).
- Kotchen, M.J. and L.E. Grant, Does daylight saving time save energy? Evidence from a natural experiment in Indiana. National Bureau of Economic Research Working Papers, 2008(14429): p. 1-36.
- Kandel, A. and M. Sheridan, The effect of early daylight saving time on California electricity consumption: A statistical analysis. California Energy Commission Staff Report, 2007. 200-2007-004.
- Department of Energy, Impact of extended daylight saving time on national energy consumption. 2008, Department of Energy: Washington, DC.
- Kamstra, M.J., L.A. Kramer, and M.D. Levi, Losing sleep at the market: The Daylight Saving anomaly. American Economic Review, 2000. 90(4): p. 1005-1011.
- Gerlach, J.R., Daylight and investor sentiment: A second look at two stock market behavioral anamolies. Journal of Financial Research, 2010. 33(4): p. 429-462.
- Coren, S., Daylight saving time and traffic accidents. New England Journal of Medicine, 1996. 334(14): p. 924-925.
- Barnes, C.M. and D.T. Wagner, Changing to daylight saving time cuts into sleep and increases workplace injuries. Journal of Applied Psychology, 2009. 94(5): p. 1305-1317.
- Wagner, D.T., et al., Lost sleep and cyberloafing: Evidence from the laboratory and a daylight saving time quasi-experiment. Journal of Applied Psychology, 2012. 97(5): p. 1068-1076.
- Gaski, J.F. and J. Sagarin, Detrimental effects of daylight-saving time on SAT scores. Journal of Neuroscience, Psychology, & Economics, 2011. 4(1): p. 44-53.
- Chmura, C., et al. Sleepbetter lost-hour economic index. 2014 7 November 2014; Available from: http://www.chmuraecon.com/blog/2014/march/06/sleepbetter-lost-hour-economic-index/.
- Downing, M., Spring Forward: The Annual Madness of Daylight Saving. 2005, Washington, D.C.: Shoemaker & Hoard. xiv, 202 p.