What? Why Would They Do That? (Daylight Savings Time)

Two weeks ago was the end of daylight savings time here in the United States, and I was talking to my wife about it.  Specifically, I was saying that I’d considered reminding my team at work to set their clocks back on Sunday, but I’d decided against it.  They’re all young, so I was the only person on the team that owned a clock that didn’t automatically reset (my microwave, if you’re curious).

“Why do you need to change the clock?” my son asked.

“Daylight savings time is coming to an end,” I told him.  “So, at two in the morning on Sunday, we set the clock back to 1 AM.”

He looked at me like I’d grown a second head.  “What?” he says, laughing.  “Why would they do that?”

Why do we do this thing?

At its core, daylight savings time exists because of an idea of “saving daylight” – pushing time around to give more light in the evening.  In theory, at least, this reduces energy consumption because people would be less likely to be at home in the longer, well-lit summer evenings.  Recent studies have been ambiguous about whether or not this works, with results ranging from a 0.5% decrease in energy use to a 1% increase in energy use.

Despite the myths, we daylight savings time was never intended to benefit farmers.  The changing time disrupts farm schedules and makes caring for animals (especially cattle) more difficult.

A history of Daylight Savings Time

The first act that created daylight savings time was the Standard Time Act of 1918, which was “[a]n Act To save daylight and to provide standard time, for the United States”.  Section 3 of the Act stipulated the following”

That at two o’clock antemeridian of the last Sunday. in March of each year the standard time of each. zone shall be advanced one hour, and at two o’clock antemeridian of the last Sunday in October in each year the standard time of each zone shall, by the retarding of one hour, be returned to the mean astronomical time of the degree of longitude governing said zone, so that between the last Sunday in March at two o’clock antemeridian and the last Sunday in October at two o’clock antemeridian in each year, the standard time in each zone shall be one how’ in advance of the mean astronomical time of the degree of longitude governing each zone, respectively.

This provision of the Act was repealed on March 19, 1919, although the bulk of the Act – which created the four time zones of the continental United States, were left in force.

A form of Daylight Savings Time returned during the Second World War, when the clocks were permanently set forward one hour for the duration of the war as a fuel rationing move.  Here’s what that Act had to say:

AN ACT To promote the national security and defense by establishing daylight saving time.

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That beginning at 2 o’clock antemeridian of the twentieth day after the date of enactment of this Act, the standard time of each zone established pursuant to the Act entitled “An Act to save daylight and to provide standard time for the United States”, approved March 19, 1918, as amended, shall be advanced one hour.

Sxc. 2. This Act shall cease to be in effect six months after the termination of the present war or at such earlier date as the Congress shall by concurrent resolution designate, and at 2 o’clock antemeridian of the last Sunday in the calendar month following the calendar month during which this Act ceases to be in effect the standard time of each zone shall be returned to the mean astronomical time of the degree of longitude governing the standard time for such zone as provided in such Act of March 19, 1918, as amended.

This was something of an exceptional version of Daylight Savings Time, lasting from February 9, 1942 to September 30, 1945.

Daylight Savings Time didn’t return in any official capacity until US Code Title 15, Chapter 6, Subchapter IX – Standard Time was passed in 1966, stating that “It is the policy of the United States to promote the adoption and observance of uniform time within the standard time zones prescribed by sections 261 to 264 of this title, as modified by section 265 of this title. To this end the Secretary of Transportation is authorized and directed to foster and promote widespread and uniform adoption and observance of the same standard of time within and throughout each such standard time zone.”  The original legislation stated that Daylight Savings Time would last from “the period commencing at 2 o’clock antemeridian on the last Sunday of April of each year and ending at 2 o’clock antemeridian on the last Sunday of October of each year”.  This was later amended by the Energy Savings Act of 2005 by

  1. by striking “first Sunday of April” and inserting “second Sunday of March”; and
  2. by striking “last Sunday of October” and inserting “first Sunday of November”.

Was the candy industry behind the most recent change?

That’s a thing that gets trotted out as a fact, yes.  Heck, I’ve been known to do it myself.  But, it seems, the truth is a little murkier.  The candy industry did participate in lobbying for the change, but the actual change was driven by a belief that it would change industry – not that it would increase candy sales (see the Energy Savings Act, above).  Various retail and sports industry lobby groups also supported the bill, so laying it all at the feet of Big Candy is a little… sour.