Changing the clock twice a year impacts more than just your sleep. Changing the clock twice a year impacts more than just your sleep. Changing the clock twice a year impacts more than just your sleep. (Photo: Romolo Tavani / Shutterstock)

8 odd facts about daylight saving time

What Ben Franklin, candy makers and 'American Idol' have to do with the shifting clocks.

It happens twice a year: Spring forward, fall back. This semi-annual shifting of the clocks occurs on different dates across the globe for a variety of reasons and has some interesting side effects. Behold, eight strange facts you may not have known about daylight saving time.

1. Ben Franklin was an early advocate of changing the clocks.

Ben FranklinYears after his infamous lightning strike, Benjamin Franklin discovered something else. (Photo: Liudacorolewa/Shutterstock)

His kite experiment may have given us electricity, but this founding father was also famous for giving us something else: Time travel. Sort of. The famous inventor first discussed changing the clocks in 1784 when he penned an essay titled “An Economical Project for Diminishing the Cost of Light” in The Journal of Paris. One of the rationales he suggested? Longer daylight hours would save on candle use.

2. It happens at different times in different countries.

Tel Aviv sunset behind a bridgeThe sun sets along the Mediterranean coast in Tel Aviv. The changing of the clocks this spring will add an additional hour of sunlight. (Photo: Protasov AN/Shutterstock)

Not everyone changes the clock on the same date, which can make for confusing calls to friends and family in other countries. For example, Brazil already changed its clocks on the third Saturday in October. Israel usually changes the clock on the last Sunday in October (the 25th this year). That means that for a few days this month, Tel Aviv will only be six hours ahead of New York City instead of seven. "There is no international authority governing timekeeping," Michael Downing, the author of Spring Forward: The Annual Madness of Daylight Saving, told From The Grapevine. "There is no logic to the confusion."

3. Candy makers and the barbecue industry enjoy it.

Brooklyn residents participate in Halloween activities.Brooklyn residents participate in Halloween activities. (Photo: Jemal Countess/Getty Images)

Longer amounts of daylight in the fall means more time for kids to go trick-or-treating on Halloween. In 2007, the United States began pushing back the time change until after the holiday. The barbecue industry is also a big proponent of the extended daylight hours. In 1986, when the U.S. added an extra month of daylight saving time, it was estimated to be worth $100 million in extra sales of grills and charcoal briquettes.

4. TV networks don't enjoy it as much.

American idol'American Idol' saw its viewership numbers shift when the clocks changed. (Photo: Kevin Winter/Getty Images)

Earlier sunsets mean more people will come home after work and settle in to a good episode of "Jane the Virgin" or a comforting "Seinfeld" rerun. So when the clocks "spring forward" and offer more hours of sunlight, people often choose to run errands and do other recreational activities after work. (Soccer practice, anyone?) TV viewership numbers usually drop each spring. Indeed, the hit singing competition "American Idol" received historic low ratings in 2009 immediately following the spring time change. According to estimates, prime-time TV shows shed 10 percent of their viewers on the Monday after the clocks are changed. "I think television networks would like it to be dark as soon as you left the office and headed home for the night," Bill Gorman, of the website TV by the Numbers, told NPR. "And maybe it started raining or snowing a lot as soon as prime time began."

5. It can cause lower SAT scores.

SAT test prep booksSAT test prep books sit on a shelf at a Barnes and Noble in New York City. (Photo: Mario Tama/Getty Images)

A fair warning for high school students: The change in clocks can mess up sleep schedules for teenagers and cause them to do poorly on the college entrance exams, according to a study in the Journal of Neuroscience, Psychology, and Economics. The researchers reported a 2 percent decrease in scores when the SAT tests were administered after daylight saving time. We assume questions about the time-space continuum were not covered on the exam.

6. Arizona and Hawaii don't participate.

Tourists at a Hawaiian beachTourists at Waikiki beach in Honolulu enjoy Hawaii's tropical climate. (Photo: Jewel Samad/AFP/Getty Images)

Arizona hasn't changed its clocks since 1968. "Interestingly enough, not observing daylight saving time seems to impact me the most when I work," Ronaldo Herreras, a 30-year-old Arizona native, told From The Grapevine. A banking analyst, Herreras said he has to come in earlier to support his clients outside of Arizona. "It makes it hard to keep a set schedule throughout the year." As for Hawaii, opting out of changing the clocks was more of a practical decision: Extending daylight doesn't help much in Hawaii's tropical latitude.

7. It saves energy (or does it?)

A lampost in a parkExtra hours of daylight mean less reliance on lamp bulbs and other artificial light. (Photo: Jack_photo/Shutterstock)

A study by the U.S. Department of Transportation showed that the country's electricity usage is cut by 1 percent each day because of daylight saving time. Although a study from the University of California, Santa Barbara found the opposite: Professor Matthew Kotchen collected data on 250,000 households and 7 million observations of monthly billing data, and estimated that – contrary to the conventional wisdom – daylight saving time actually increased electricity consumption between 1 and 4 percent.

8. It's singular.

Man holding up single finger.(Photo: Mimagephotography/Shutterstock)

It's called daylight saving time, not savings. "There is a lot of contention over words that are used so often as a colloquialism that they eventually become part of acceptable use,” Sharon Feingold, of accent and dialect training company Babel Consultants, told From The Grapevine. "Certain friends of mine refuse to accept those changes, even if Merriam-Webster has adjusted the spelling or definition. Admittedly, I only learned a few years ago that saying ’so anyways' is actually a transgression, and the word is actually ‘anyway.' So it doesn’t surprise me that savings has, in a sense, become universally adopted, to the dismay of many wordsmiths."


Photos and SlideshowsPhotos and Slideshows

Related Topics: Lists

8 odd facts about daylight saving time
What Ben Franklin, candy makers and 'American Idol' have to do with the shifting clocks.