Congressional Research  

98-99 C Daylight Saving Time


NUMBER: 98-99 C
DATE: February 9, 1998
TITLE: Daylight Saving Time
AUTHOR: Heidi G. Yacker
DIVISION: Congressional Reference Division


Currently, in most parts of the United States, timepieces are moved forward one hour in the spring and back one hour in the fall to provide an extended daylight period during the summer months. This is known as Daylight Saving Time (DST). Much debate and many changes led to this present practice. This report provides a brief history of the issues surrounding DST, an outline of the legislation that created and modified it, and a list of references to more discussions. Whenever the law or regulations governing DST change in the United States, this report will be updated.

Development of Daylight Saving Time

Currently, Daylight Saving Time (DST) is observed in the United States from 2:00 a.m. on the first Sunday in April until 2:00 a.m. on the last Sunday in October. The following states and territories do not observe DST: Arizona, Hawaii, part of Indiana, American Samoa, Puerto Rico, and the Virgin Islands.

Daylight Saving Time (DST) is not a new concept. In 1784, when Benjamin Franklin was Minister to France, an idea occurred to him: in that part of the year when the sun rises while most people are still asleep, clocks could be reset to allow an extra hour of daylight during waking hours. He calculated that French shopkeepers could save one million francs per year on candles. In 1907, William Willett, a British builder, Member of Parliament, and fellow of the Royal Astronomical Society, proposed the adoption of advanced time. The bill he introduced was reported favorably, asserting that DST would move hours of work and recreation more closely to daylight hours, reducing expenditures on artificial light. There was much opposition, however, and the idea was not adopted.

During World War I, in an effort to conserve fuel, Germany began observing DST on May 1, 1916. As the war progressed, the rest of Europe adopted DST. The plan was not formally adopted in the United States until 1918. 'An Act to preserve daylight and provide standard time for the United States' was enacted on March 19, 1918 (40 Stat 450). It both established standard time zones and set summer DST to begin on March 31, 1918. The idea was unpopular, however, and Congress abolished DST after the war, overriding President Wilson's veto. DST became a local option and was observed in some states until World War II, when President Roosevelt instituted year-round DST, called 'War Time,' on February 9, 1942. It lasted until the last Sunday in September 1945. The next year, many states and localities adopted summer DST.

By 1962, the transportation industry found the lack of nationwide consistency in time observance confusing enough to push for federal regulation. This drive resulted in the Uniform Time Act of 1966 (P.L. 89-387). The Act mandated standard time within the established time zones and provided for advanced time: clocks would be advanced one hour beginning at 2:00 a.m. on the last Sunday in April and turned back one hour at 2:00 a.m. on the last Sunday in October. States were allowed to exempt themselves from DST as long as the entire state did so. If a state chose to observe DST, the time changes were required to begin and end on the established dates. In 1968, Arizona became the first state to exempt itself from DST. In 1972, the Act was amended (P.L. 92-267), allowing those states split between time zones to exempt either the entire state or that part of the state lying within a different time zone. The newly created Department of Transportation (DOT) was given the power to enforce the law. Currently, the following do not observe DST: Arizona, Hawaii, the part of Indiana in the eastern time zone, American Samoa, Puerto Rico, and the Virgin Islands.

During the 1973 oil embargo by the Organization of Petroleum Exporting Countries (OPEC), in an effort to conserve fuel Congress enacted a trial period of year-round DST (P.L. 93-182), beginning January 6, 1974, and ending April 27, 1975. From the beginning, the trial was hotly debated. Those in favor pointed to the benefits of increased daylight hours in the winter evening: more time for recreation, reduced lighting and heating demands, reduced crime, and reduced automobile accidents. Opposition was voiced by farmers and others whose hours are set by the sun rather than by the clock. With later sunrises and sunsets, they were unable to arrive at work on time after morning activities or participate in evening activities. Another major concern was children leaving for school in the dark. The Act was amended in October 1974 (P.L. 93-434) to return to standard time for the period beginning October 27, 1974, and ending February 23, 1975, when DST resumed. When the trial ended in 1975, the country returned to observing summer DST (with the aforementioned exceptions).

DOT, charged with evaluating the plan of extending DST into March, reported in 1975 that 'modest overall benefits might be realized by a shift from the historic six-month DST (May through October) in areas of energy conservation, overall traffic safety and reduced violent crime.' However, DOT also reported that these benefits were minimal and difficult to distinguish from seasonal variations and fluctuations in energy prices.

Congress then asked the National Bureau of Standards (NBS) to evaluate the DOT report. NBS found no significant energy savings or differences in traffic fatalities. It did find, however, statistically significant evidence of increased fatalities among school-age children in the mornings during the test period, although it was impossible to determine if this was due to DST.

During the 96th, 97th, and 98th Congresses, several bills to alter DST were introduced, and the debate continued. Final action came in the 99th Congress with the enactment of P.L. 99-359, which amended the Uniform Time Act, changing the beginning of DST to the first Sunday in April and having the end remain the last Sunday in October. Since then, bills have been introduced to move the beginning of DST to the last Sunday in March and the end to the first Sunday in November. No action has been taken on these bills.

Changing an Area's Time Zone or Moving an Area On or Off DST

Moving a state or an area within a state from one time zone to another requires either a public law or a regulation issued by DOT. In the latter case, DOT recommends the following procedure. The request should be submitted by the highest political authority in the area in question. For example, the governor or state legislature generally makes the request for a state or any part of the state; a board (or boards) of county commissioners may make a request for one or more counties. If the request is made by a legislative body, it must be accompanied by certification that official action has been taken by that body.

The request should document evidence that the change will serve the convenience of commerce in the area. The convenience of commerce is defined broadly to consider such circumstances as the shipment of goods within the community; the origin of television and radio broadcasts; the areas where most residents work, attend school, worship, or get health care; the location of airports, railway, and bus stations; and the major elements of the community's economy.

The General Counsel of DOT considers the request and, if it is found that a time zone change might benefit commerce, a proposed regulation is issued inviting public comment. Usually a hearing is held in the area so that all sides of the issue can be represented by the affected parties. After analyzing the comments, the General Counsel decides either to deny the request or forward it to the Secretary of Transportation. If the Secretary agrees that the convenience of commerce would benefit, the change is instituted, usually at the next changeover to or from DST.

Under the Uniform Time Act, moving an area on or off DST is accomplished through legal action at the state level. Some states require legislation while others require executive action such as a governor's executive order. Information on procedures required in a specific state may be obtained from that state's legislature or governor's office. Although it may exempt itself, if a state decides to observe DST, the dates of observance must comply with federal legislation.

Past Legislation

P.L. 89-387, April 13, 1966, Uniform Time Act of 1966

Established uniform standard time to be observed in established time zones. The standard time would be advanced one hour within each time zone beginning at 2:00 a.m. on the last Sunday in April and turned back one hour beginning at 2:00 a.m. on the last Sunday in October. States were allowed to exempt themselves as long as the entire state was exempted.

P.L. 92-267, March 30, 1972, [Uniform Time Act Amendments]

Allowed states split by time zone boundaries to exempt the entire state or that part of the state in a different time zone from DST. The states affected are: Alaska, Florida, Idaho, Indiana, Kansas, Kentucky, Oregon, Nebraska, North Dakota, South Dakota, Tennessee, and Texas.

P.L. 93-182, December 15, 1973, Emergency Daylight Saving Time Energy Conservation Act of 1973

Established a trial period for year-round DST beginning January 6, 1974, and ending April 27, 1975.

P.L. 93-434, October 5, 1974, [Emergency Daylight Saving Time Energy Conservation Act]

Amended P.L. 93-182 to restore standard time from November 1974 through February 1975.

P.L. 99-359, October 8, 1986, [Fire Prevention and Control Authorizations Act]

Amended the Uniform Time Act of 1966 to begin DST on the first Sunday in April. The end of DST would remain at the last Sunday in October.


Bartky, Ian R., and Harrison, Elizabeth. Standard and daylight-saving time. Scientific American, v. 240 (May 1979): 46-53. T1.S5

Chapman, Fern Schumer. Business's push for more daylight time. Fortune, v. 110 (Nov. 1984): 149. HF5001.F7

Clark, Edie. Daylight nuisance time. Yankee, v. 60 (April 1996): 14. AP2.Y25

Coren, Stanley. Daylight savings time and traffic accidents. New England Journal of Medicine, v. 334 (April 4, 1996): 924. R11.B7

Sleep sliding away. Saturday Night, v. 111 (April 1996): 19, 20, 22. AP5.S27

Early to bed, early to rise. Time, v. 127 (June 2, 1986): 27. AP2.T37

Ferguson, Susan A., et al. Traffic accidents and Daylight Saving Time. New England Journal of Medicine, v. 335 (August 1, 1996): 335. R11.B7

Reduction in pedestrian and vehicle occupant fatal crashes with Daylight Saving Time. Arlington, VA, Insurance Institute for Highway Safety, 1993. 15 p.

New look at extended daylight-saving time. U.S. News and World Report, v. 99 (December 2, 1985): 53. JK1.U65

O'Neill, John. Losing more than one hour. New York Times, v. 146 (April 1, 1996): B11.

U.S. Congress. House. Committee on Energy and Commerce. Daylight Saving Extension Act of 1985. Report to accompany H.R. 2095, including cost estimate of the Congressional Budget Office. Washington, GPO, 1985. (99th Congress, 1st session. H.Rept. 99-185).

U.S. Department of Transportation. The Daylight Saving Time study. A report to Congress. Washington, GPO, 1975. 2 v. HN49.D3U65 1975

Vol. 1, final report of the operation and effects of daylight saving time.

Vol. 2, supporting studies: final report of the operation and effects of daylight saving time.

U.S. National Bureau of Standards. Review and technical evaluation of the DOT Daylight Saving Time study. Prepared for the Chairman, Subcommittee on Transportation and Commerce, Committee on Interstate and Foreign Commerce, U.S. House of Representatives. Washington, GPO, 1976. p. 125-351. KF27.I5589 1976L

Appendix to hearing on the Daylight Saving Time Act of 1976, 94th Congress, 2nd session. Serial no. 94-109.

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