At 2 a.m. on October 29, groggy Americans will turn their clocks back one hour, marking the end of
Daylight Saving Time (DST).
The federal law that established "daylight time" in this country does not require any area to observe daylight saving time. But if a state chooses to observe DST, it must follow the starting and ending dates set by the law. From 1986 to 2006 this has been the first Sunday in April to the last Sunday in October, but starting in 2007, it will be observed from the second Sunday in March to the first Sunday in November, adding about a month to daylight saving time.
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