Permanent time observation in the United States

Establishing either permanent standard or daylight saving time (DST) eliminates the practice of semi-annual clock changes, specifically the advancement of clocks by one hour from standard time to DST on the second Sunday in March (commonly called "spring forward") and the retardation of clocks by one hour from DST to standard time on the first Sunday in November ("fall back"). The existing practice of switching the clocks twice a year is unpopular, with only about 20% of Americans preferring it.

Source: Wikipedia — Permanent time observation in the United States (CC BY-SA 4.0)