Daylight savings time began at 2 a.m. this morning, causing everyone to lose an hour of sleep as they set their clocks forward an hour. Although an hour of sleep was lost, an extra hour of daylight has been gained from now until Nov. 3, when the clocks will roll back an hour.

Daylight savings time was first introduced during the World Wars in an attempt to conserve energy. In 1966, The Uniform Time Act was passed, standardizing daylight savings time. According to a study performed by the Department of Energy, daylight savings time decreases U.S. electricity usage by about half a percentage point per day.

Not everyone in the U.S. observes daylight savings time. Arizona (excepting the Navajo Nation), Hawaii, Puerto Rico, Guam, American Samoa and the Virgin Islands all stay on “standard time” throughout the entire year. Their reasoning for not observing daylight sayings time has to do with the excessive amount of heat and sunlight they already receive – negating their need for the extra hour.

Oddly enough, the midwestern state of Indiana long stalled in observing daylight savings. It was not until 2005 that the state passed a new law, thereby adopting the energy saving measure. Indiana is also split between Central Time and Eastern Time, with 18 counties observing the former and the remaining 74 observing the latter.

It’s only been since 2007 that daylight savings time has begun on the second week of March and ended the first Sunday in April. It previously began three weeks later and ended one week earlier.

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