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To some degree, we may have Benjamin Franklin to thank.

Franklin, who penned the proverb "Early to bed and early to rise, makes a man healthy, wealthy and wise," was among the first to suggest the idea. In a 1784 essay he wrote that adjusting the clocks in the spring could be a good way to save on candles.

The practice of changing the clocks has had a somewhat bumpy history in the United States. It was first established in 1918, but then repealed a year later. During World War II, the country again took up the practice to conserve energy from 1942 to 1945

In 1966 the United States officially adopted the Uniform Time Act of 1966, which outlined Daylight Saving Time to begin on the last Sunday of April and end on the last Sunday in October.

The Energy Policy Act of 2005 mandated a change to the observed dates so now DST begins at 2 a.m. on the second Sunday of March and ends at 2 a.m. on the first Sunday in November.

Incidentally, states do not have to comply with the act and, in fact, two states, Arizona and Hawaii, do not.

So do we really economize, as Benjamin Franklin said we would, by adjusting our clocks? It appears, in our modern world, not really.

Although a U.S. Department of Transportation study in the 1970s found that daylight saving trimmed electricity usage by about 1 percent, later studies have shown that the savings is offset by air conditioners running in warmer climates.

It may not all be for naught, however. Another study, performed in 2007 by the RAND Corporation found that the increase in daylight in spring led to a roughly 10 percent drop in vehicular crashes.