夏令时实行100年，其好处仍然不明确

从3月11日晚上开始，美国人民就得把闹钟调快一个小时了，至于智能手机、平板电脑和计算机什么的，则会自动将时间调快一个小时。这种做法又称“夏令时”，最早可以追溯到1918年3月的美国。继美国之后，德国、英国等地也相应建立了夏令时制度。

美国的夏令时是由第28任总统伍德罗·威尔逊推动建立的，其初衷是为了让大家充分利用自然光，好节约能源打赢第一次世界大战。此后的几十年，夏令时制度逐步在各州得到推广，最终在60年代在国家层面确定下来。

一战结束后，另一种支持夏令时的观点出现了。据《史密森学会杂志》报道，百货商店的老板们是很支持夏令时的，因为人们下班后如果天还没黑，就会有很多人选择去购物。该政策也对高尔夫等运动的发展有益。

不过这些观点也并非完全能站得住脚。虽然美国能源部有研究称夏令时令美国的能源消费略有下降，但其他研究却“打脸”了能源部，表明夏令时实际上增加了能源消费和排放。2016年摩根大通的一项研究也显示，虽然在夏令时期间，人们的消费支出会有所增加，但一旦恢复到冬令时，消费支出又会显著下降，基本抵消了夏令时对消费的刺激。

很多人认为夏令时对农业有好处，然而恰恰相反，几十年来，美国的农民们一直呼吁取消夏令时。

因此，夏令时对经济的刺激或许只是“看上去很美”。夏令时的确对社会有些积极贡献——比如抢劫犯罪的少了些。但由于夏令时扰乱了人们的睡眠习惯，因而它也增加了人们患心脏病和遭遇工作事故的风险。

总之，证据的天平似乎开始向反对夏令时的一方倾斜。不过要想说服国会取消夏令时制度也是不容易的——近年的民调表明，大多数美国人还是支持夏令时制度的，哪怕他们每年都有一两天因为倒时差而睡不好觉。（财富中文网）

译者:朴成奎 

Some tonight, you will either manually set your clocks ahead an hour, or (more likely) your various smartphones, tablets, and computing devices will adjust themselves for you. Those devices will be carrying forward a practice that dates to March of 1918, when the U.S. — following Germany and Great Britain – implemented a plan for Daylight Saving Time.

The initial justification for the policy, implemented by Woodrow Wilson, was that it would save energy that could go towards helping fight World War I. The same rationale would be used for the expansion of Daylight Saving in later decades, including its national formalization in the 1960s.

Following World War I, though, a different rationale surfaced. According to Smithsonian Magazine, department store owners pushed for the policy to continue, since more people shopped after work when it was light out later. The policy has also benefited sports like golf.

Those motives haven’t proven entirely durable. One study found that Daylight Savings actually increased home energy consumption and emissions, though a conflicting Department of Energy study found a small but significant decline. More damning was a 2016 J.P. Morgan study finding that, while there’s some boost to spending when Daylight Savings Time goes into effect, it’s offset by a substantial drop when clocks are switched back.

And Daylight Saving does not, contrary to widespread myth, particularly benefit farmers. In fact, farmers lobbied against it for decades.

So the commercial motives for Daylight Saving Time may not be all they’re cracked up to be. Some subtler positive effects have been measured, including declines in robberies – but so have increases in heart attacks and workplace accidents, thanks to the effects of sleep disruption.

On balance, the objective evidence against Daylight Saving Time seems to outweigh arguments in its favor. But groups lobbying to eliminate it have an uphill battle – polls in recent years show a majority of Americans still support the policy, even if it costs them sleep once a year.