when was time change started
The Uniform Time Act of 1966 provided the basic framework for alternating between daylight saving time and standard time, which we now observe in the United States. But Congress can't seem to resist tinkering with it. For example, in 1973 daylight saving time was observed all year, instead of just the spring and summer. The system of beginning DST at 2 AM on the first Sunday in April and ending it at 2 AM on the last Sunday in October was not standardized until 1986. The rules changed again in 2007. DST now begins on the second Sunday of March and ends the first Sunday in November.