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Dashed edge = started before, or continues beyond, this day
Events on Sunday 31 March 1918 1
1918Daylight saving time introduced in the United StatesUS adopts clock changes to conserve wartime fuelThe Standard Time Act took effect, introducing daylight saving time across the United States for the first time to save fuel during World War I. Clocks were set forward one hour on the last Sunday in March. The measure proved unpopular and was repealed the following year, though it was later reinstated permanently in 1942 and after.