The end of daylight savings time occurred Sunday November 6 for most of the United States. The Daylight Saving Time Energy Conservation Act of 1973 was signed by Richard M Nixon during the energy crisis.
The time change isn’t observed by Hawaii, most of Arizona, Puerto Rico, the Virgin Islands, American Samoa, Guam and the Northern Marianas.
WCVB provides a nice overview of health concerns regarding being awake during hours of less sunlight.