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After losing an hour of executive time to “springing forward” his clock an hour over the weekend, President Donald Trump voiced his support Monday to eliminate states’ legal requirement of “falling back” an hour each year.

“Making Daylight Saving Time permanent is O.K. with me!” Trump tweeted.

One of the most common justifications for the time switch is the presumption that by extending summer daylight later into the evening, Americans use less energy.

It was the reason Congress used in enacting Daylight Saving Time during World War I and again after the United States joined WWII, according to author David Prerau, who wrote a book which traced the history of the shift on Daylight Saving Time.

But a 2008 Department of Energy study found that daylight saving time reduces annual energy use by about 0.03%. And a study that same year from the University of California-Santa Barbara found it might even increase energy consumption.

And while it’s a popular belief that Daylight Saving Time was created to help farmers get their harvests, farmers actually vociferously fought the proposals, arguing they cut productivity and made life overall tougher for them, according to Prerau.

Ending Daylight Saving Time would require congressional approval, but it’s already been bolstered by several Florida Republicans in Congress who sponsored legislation last year that would make daylight saving time permanent nationwide. The legislation died in Congress, but Florida Republican Sen. Marco Rubio reintroduced the legislation last week.

Last year, then-Florida Gov. Rick Scott signed a law to make Daylight Saving Time permanent in the Sunshine State, but the act has yet to be signed off by Congress – putting Florida’s switch on hold.

Americans have observed Daylight Saving Time switch for a little more than 100 years, but the amount of time which they have been observing when the nation “falls back” an hour has continued to shrink.

The Standard Time Act established time zones and daylight saving. Daylight saving was repealed in 1919, but continued to be recognized in certain areas of the United States.

The Uniform Time Act of 1966 established the system of uniform Daylight Saving Time throughout the United States. The dates were the last Sunday in April to the last Sunday in October.

Today, most states observe eight months of Daylight Saving Time and four months in standard.

Currently, Hawaii and most of Arizona do not follow the Daylight Saving Time switch, and neither do the US territories of Guam, Puerto Rico, Virgin Islands and American Samoa.

CNN’s Michael Pearson contributed to this report.