How Daylight Saving Time Works

basis twice. Sometimes it's important stuff like you know, um, the digestion. That's right, good thing which comes out next? Right? All right? Introman, Oh, I'm sorry? Am I am I stalling? Yeah? Okay, frankly, Chuck, have you ever heard of a methuselah? Trust? No, but

of something being old? Uh, well you're not old. Instead, a say, a bequeathment grant that you've put in a an account earning compound interest for five hundred or a thousand or a hundred years, should conceivably, were it's still legal, grow into a staggering amount of money, very like, very quickly.

For example, Um, there was a guy who you might have heard of named Ben Franklin Benny Ben Franklin Uh in his will left a thousand pounds each to the city of Boston in the city of Philadelphia, both of which he considered his hometowns UM and these these monies were meant to stay in a private trust that earned compound interests, and by Franklin's reckoning, um within so after a hundred years in eighteen nine that it was supposed to be cracked open, a bit was supposed to be

taken out, and then the rest was supposed to be left in until nine years after his death. So by his reckoning it would each city would get about the equivalence six million dollars apiece UH by nine, which is when it was supposed to and and finally mature. UM. It didn't quite work out. Franklin's calculations didn't take into account lawsuits to stop this, to stop the idea of him enthuselah trust in general, UM, trustees, fees, lawyers, fees, all this stuff. So what it came down to was

about three and a half million each. So he's off the market a little bit. But he made his point, which was, if you put a grand in and you have enough foresight, you can give some money to the city of Boston. Did that really happen? Yeah, they got there, They got their three and a half mill Yeah each townded Um. What this demonstrate is probably more than anything, though, is that Franklin was, above all else, an idea man. Right.

He was pretty good. I mean, he invented spectacles. He had like some really good uh some good inventions under his belt, the electric kite. But more than anything else, he was all about ideas. And he was more aware than anybody that his ideas weren't always he didn't see him through to fruition all the time. Not not all ideas were meant to be. But another good example of that is his idea for daylight savings time. He was the guy that came up with this saving daylight saving time.

I think most people say savings, but it is in fact saving. But we're gonna mess up and say savings. So yeah, just prepare for that, s people. Franklin was an ambassador to France, which is a pretty crushed job back then. I'm sure the Enlightenment. Come on, it's his job now. Um. Woke up one morning all this uh fellow Parisians were sleeping and he said, hey, we should change the time and get these people up earlier. Did

he talk like he was from Jersey. He basically proposed it in an article, but it's generally dismissed his satire. But it wasn't a real idea, right. His whole idea was to um that basically everybody was like sleeping in light while it was still daylight and then staying up late long after sunset. It was a waste of daylight. A great way to fix this is to say, let's get everybody up at the crack of dawn, and we'll do that by shooting off cannons that wake everybody up.

It was sort of a jab at the French, a friendly jab. Well, he was a friend of the French, but like I said, generally dismissed his satire. Not really like the seed of the idea for daylight saving. No. But other people about a hundred or so years later

came up with similar things and they meant it. And it's I don't know if we can say that Franklin didn't mean it, but he was just he He didn't think it was a very important idea necessary, but it's so ingrained in our society here in the United States, here in North America, and most likely if you're listening to this in Europe or Australia. You know what we're talking about all over the world. Really, um that it You're you're kind of like, oh yeah, daylight savings. I mean,

it's peculiar, but of course we're gonna do it. Of course it makes sense. Um, these this is from people who really can't even tell you whether it's spring forward or fall back. So let's let's set that straight right now, because I think if we just stopped there and said it is spring forward where you said the clock forward an hour, and it's fall back where you said the clock back an hour, we've just done a tremendous public service.

People really not remember that. I'm among them. Really, yeah, I will always remember it now because I've studied this article. But no, I always had trouble with it. Well, that's why they say spring forward, fall back. You can also fall forward and spring back. You can't spring back. I can't hold on, Josh, Josh, just sprung back, sprung back. All right, Well, here's the other public service announcement here

in the US. Second Sunday in March. You're gonna spring forward the first Sunday in November, you're gonna fall back. I didn't know that, because every year I'm on the internet's going, well, when do we do this? When do we do it? I didn't. I thought it fluctuated. Second Sunday in March, first Sunday in November. Boom. Yeah, I thought it fluctuated as well too. It's yeah, um, it's standard now thanks to a lot of UM legislation that's taken place over the over the years here in the

United States. UM. Most recently, the Energy Policy Act of two thousand five set the rules as you just described them. Right. We should also say, chuck to our friends in South America, you have the opposite. We're not exactly sure when it starts for you, but we can tell you that you do spring forward and fall back. No, fall forward and spring back, because it's the the seasons are the opposite. So they go on to daylight savings time in the fall and then change it. They go off of it

in the spring. And also one more thing, uh, daylight saving time, right is not? I find it confusing in that the mind wants to say it's it's like daylight time saving it's like daylight saving time, right, like your time saving but really it's daylight saving time, so it's like a period of the year. So I've always had trouble wrapping my mind around how they're just saving daylight. Everything about this is so confounding. I know, because I'm one of those people that's like what the clock says

is arbitrary in a way. Unless you have a shift job, Um, you would have made a great farmer. Yeah. That's kind of bunk too from what I hear. Okay, so let's talk about this, man Um. You just gave the deets on when to do it. Um. In the United States, it's the Energy Policy Act of two thousand five that establishes that. But if you are Arizona or Hawaii or Guam and you say, I don't want this to apply to me already feel cut off enough from this country, Um,

from the rest of the world. I'm going to apply for an exemption. You're probably gonna get it. Yeah. Indiana has had a mixed history with daylight saving Uh. They've kind of fluctuated back and forth over the years, and at times only some counties had it and some didn't, And they finally went all in I think so recently. Yeah, if you're an Indiana, you know what I'm talking about. Um,

And it's not just the United States. Apparently, as a two thousand and eight, seventy six countries observed daylight savings time. They also seventy, but I don't know which sources newer, so we'll go with seventy to seventy six. Just after reading this, I could see six countries falling. Yeah, I mean it's a very it's a surprisingly contentious thing setting the clock back an hour basically. I saw one source that calls it the arrogance of humanity to to set

time period. Yeah, well no, to adjust the clock. It's like it is now two and not one, right exactly, And it is a little bit loony if you think about it. Um. I think Japan, India, and China are the only major industrialized nations who do not observe. And it's getting more and more difficult to to um be a country like that in this globalized world to not daylight savings something. I mean, it's kind of problematic. Sure, yeah, imagine the that's why most countries do it now, well

not most, but a lot. So Europe has long observed what's called summertime. Um. But it wasn't until that the EU said hey, let's all just stop this patchwork thing. Here's the standards now, um and it's uh. The European Union says it runs from daylight saving time, the time of daylight saving summertime. Yeah, it's the last Sunday in March to the last Sunday in October. That's the the EU. Yeah, good for them. No. Um. We you mentioned earlier that

another couple of guys that proposed this. Um. One of them was a New Zealander named George Vernon Hudson, and he was actually the first dude to genuinely propose this, and he gets overlooked a lot of time by the other guy we'll talk about. But Hudson was an entomologist and astronomer and he had a shift job that allowed him I guess he worked at night because allowed him extra daylight hours that his friends weren't getting. He go out and hunt for bugs and he was like this

is great. He's like, we ought to really try and do this. But William Willett of England is the guy that a lot of people credit with it, and I think it's because it was kind of his passion in life, Like he really really tried to get this push through. Yeah, he was an avid golfer. And his whole premise for it was that it would extend time for leisure after work, after everybody got done working for the day, they're still daylight hours. The links um. And he wrote a pamphlet

that's online. It's called The Waste of Daylight. It's online and its entirety if you search that um. And he lobbied the House of Commons to institute this, and in nineteen o eight they officially said nah. But he kept lobbying him until his death. And I think the twenties died in nineteen fifteen actually, so he did not get to see it because a year later, insultingly enough, a year later it was it was brought on in England

thanks to a little something called World War One. Yeah, and actually it was Germany that was the first country to ever institute daylight savings time. Yeah. They called it wartime though, Yeah, so did FDR later on. Yeah. Um, but the Germans, the Germans started it. The English quickly saw the value and it and they started it. And it was all the preserved coal supplies during the war, um, because if you or were up earlier, you'd be tired earlier and you wouldn't stay up as late earning precious

coal needed to pound the Kaiser into oblivion. That's right. And uh, a lot of a lot of nations got on board because of World War One, thirty one in total, including the US, and then World War Two. Well after the war, I think most of these countries got rid of it. It was just for war. And then World War two came around, the same thing happened, but in more abundance. Fifty two nations this time. Right in the US actually kept daylight savings year round for three full

years uninterrupted, from what is it February September. And apparently FDR he called it wartime too. He had no problem with it. He was just going to leave it like that indefinitely. Um. And he finally acquiesced to farmers, which, um, if you know much about farmers at that era, they were really a active at striking, overturning like um scab trucks, and like dealing with communists and like being pro communist um. And they were a force to be reckoned with. They

called it God's time did they really. Yeah, we'll talk more about the farmers in a minute. UM. Go on. Uh, well, we we had it for three years solid, like you said, and then after the war they said, you know what, you don't have to do it, but it's up to your state if you want to keep doing this or not. Some did, some didn't. So that's the history. Actually, no, it keeps going in nineteen sixty six. History does keep going, doesn't it. So the states are it's all patchwork and

everybody's just kind of doing what however they want. But we have this thing called the Interstate system that comes about, which links states more and more and there's more trade, and really people need to know what time it is in another state that they're sending stuff to UM. So the Uniform Time Act of nineteen sixty six finally said you guys can decide whether you want to do it, but if you're gonna do it, you have to do

it along these guidelines. UM. And it stayed that way uninterrupted until except for the arab Um oil embargo, where the US said, you know, we're gonna extend the daylight savings to UM through winter as well. Yeah, I went from six months to eight months uh in nineteen seventy three because they found that doing so saved the equivalent of ten thousand barrels of oil a day in six hundred thousand in those two years. So that's what they said it is Is it true? Who knows about that?

Definitely up for debate. Whether it's say, ten thousand barrels of oil a day, I'm sure it's for debate. The weird thing about daylight savings is it's largely been intuitive for decades. It was practiced for decades before anybody finally put it to the test. Well, the whole point behind it is this chuck that there are more people asleep at sunrise and more businesses are closed at sunrise than

at sunset. So if you look at electrical demand right um, as a whole over the course of a single day, you're gonna see in the afternoon, in the evening it starts to peak if you take an hour. If you take the whole day and shift it backward by an hour, people are gonna get up earlier, and it's going to spread that electrical demand over the day. They're also gonna go to bed earlier, so they're gonna use lamps less

they're gonna stay up less late to watch TV. UM, so the overall demand should decrease to And this is the whole reason that daylight savings time has always been UM kind of championed by most people. That's the whole reason that they want you to think, Well, that's part of it. The other is to get people outside more. Yeah. I mean I read up on this and what I found out was that it really comes down to money.

They want you to to spend the money more. Yeah, and that is going to happen more if you're out and about chopping or playing golf, exactly like the golf lobby in eighty six, the last time before two five, then anybody tinker with it, Reagan said in Public Law and ninety nine he started at the first Sunday in April, which was where before in nineteen sixty six it was from the last Sunday in April, so a full month

he added to daylight savings time. Um. But the golf Lobby said that an extra month or an extra hour. I think an extra month was like four million dollars to just that industry alone. I don't know seither. Yeah,

money talks, uh. And the reason I say that that's the main reason is because they've done studies and in fact, in seventy three when they did the oil embargo, they didn't just study oil barrels, they studied utilities and they found that it's a pretty negligible difference about one percent energy savings. But that's for the whole country. That's a lot. That is a substantial amount of that's a lot. See

I read it's negligible. So say so, say it is one percent, Say it is negligible, but say that it's zero percent. If you don't do anything, you automatically have said, well there's a there's a savings and energy, especially in this eco conscious society that we're growing into. Um, that's it right there, Okay, daylight saving time, do it. You will save one percent of all the energy expended. Fine, do it. It's better than not right. What else could

possibly go wrong? And I was very surprised from this article to find that there's actually counter arguments todaylight saving time. Well, yeah, because they basically I think people have challenge the studies. That's what I've seen. In two thousand one, they did another study the California did where they actually doubled it to a two hour shift and in the end they found it, uh, electricity savings of about point oh three for the year, right, which is substantially less, But you

can also say it's still better than nothing. Why not just do it. There's also other arguments to things like, um, there's fewer traffic accidents in the evenings because it's lighter out, that's what they say on the evening commute. Um, crime is decreased because criminals preferred darkness. And if you're out taking a walk after work and it's light out still,

you're probably not going to get mugged. Um. And then of course the golf industry said everybody needs to get off their rears and get outside and play more golf, golf fever catch it, and um, they are big on that as well. Well, I got most of my info you should know from that Skeptward guy. Let's hear it, Dunning, Well, no, that's what he said. He said, basically, it's all about money. He said, don't be foolded into thinking this is some energy plan. And he said that the numbers are suspect.

And then it really comes down to spending money as a as a consumer. I'm sure it does. But the other. The other aspect of it, the you know who's the biggest against it now these days? They used to be farmers. Well, he said, that's bunked too. He bunks everything though. So here's the thing farmers. From what I understand it used to be farmers. And I've seen this elsewhere that farmers had a problem with it because daylight savings added a

day and an hour under their day. They had to get up with the with the at the crack of dawn, no matter what time it was. So if it was actually if they had an extra hour, they had to extend their business hours because they had to deal with the public who was running on an hour later time. So farmers hated daylight savings and they railed against it.

That's my understanding with modern technology that that where a lot of the farm processes are automated, they don't have to worry about the the sun time or God's time as much. They're not as opposed to it. The problem is with airlines now when they're flying to places that don't have daylight savings, they apparently have a lot more trouble getting a slot at an airport when the time doesn't quite match up because the airport's like, we're not going to the trouble of figuring this out. Go lobby

your government to stop screwing with time. So apparently that's the big industry that's opposed daylight savings right now. Interesting. Yeah, um, like I said, though, he's that's his job. He's the skeptalid debunking. He said. The farmer thing is he thinks is somewhat of a myth because he can't find any He said, all the sources are the exact same and he can't find any like origin source that he thinks is valid. That's a that's pretty good evidence that something

is a myth. But he's trying to prove a negative. He should be opposed to that. Maybe he is. Huh m hm uh. There was a new study though, um recently by a guy named Matthew Coaching. He's an economist at cal Goberts and um, you know, I said, Indiana has kind of been back and forth over the years, with like half the state doing it. When they finally went all in and oh six, he said, hey, it's a great opportunity to check this out and study it. And he found that it led to a one percent rise.

He figured that lamp usage went down overall across the daylight savings, but that there was a peak in energy demand that was an increase over when you don't observe daylight savings in the fall when it was cold in Indiana in the form of heating, like people had their heat went up because they weren't under the blankets as early right as when they when they just observe standard time year round. And that actually cost nine million dollars

for the state. Well, I think that's part of dunning thing too, is these studies that were done in the seventies, they didn't have you know, computers and iPods and Blu ray players, and we have way more things besides lamps these days to take into account, and air conditioners and things like that. So he's saying it's kind of an outdated there are no lamps in the seventies and outdated

model the U and daylight savings. Chuck also kind of strikes me as like a really good example of for every action, there's an equal and opposite reaction, So like there's fewer fender benders during the evening commute, But apparently parents are also like parents groups are also a post daylight savings in part because kids accidents involving kids waiting for the bus in the dark or mornings increase, and then crime goes down during the summer, but then it

increases in the fall. Now there's no there's no figures to support that necessarily. But there's also the only study ever conducted about how daylight savings creates a decrease in crime was a single study of the District District of Columbia in the seventies that found a ten percent reduction, but no one's ever backed it up. Yeah, well, and think about it too. Carrex are good for industries like tow trucks and mechanics, the toe truck lobby, auto industry

that wants to sell you a new bumper. I don't know, but it does everything. You're right, Everything hasn't an opposite reaction. And also apparently chronobiologically, it can be very problematic for us. So says was he German? Yeah, I didn't see his name. He's just referred to as a German chronobiology. I couldn't

find him or her. Yeah, that's true. He or she says that your body never even adjusts period to the circadian rhythm and so you're just out of whack for eight months out of the year, or I guess it depends on which one he thinks is right. So yeah, and the big problem is going back and back, like

going back and forth. Like if we all just said, okay, the whole world's gonna set their clocks back one hour forever and that will be referred to from here on out as the hour the moment, and then we're just gonna forget about daylight saving time, it would conceivably have the same effect, right, but it would not have that

jet lag problem that the German chronobiologist describes. Um and even worse, there's other people that propose um it extended daylight savings through throughout the throughout the year or throughout the winner as well. Right, if we did that once eight could conceivably be fine. Our bodies could adjust. It's

going back and forth. Other people are proposed double daylight savings, where you go back two hours, which would probably reak havoc if are if the chronobiologist is correct, and there's actually data that supports this idea that like our bodies are disrupted by it, like the Swedish heart attack study. Yeah, I'm sure they are. I never thought of it as losing an hour though, because it happened at two am on Sunday and I would just wake up and whatever

the clock said is what it said. Yeah, I never felt like, you know, I guess I don't get up Sunday morning at seven for a shift job. No, that's a big part of it. I saw in the consumers some guy wanted to know about getting paid um on because he worked at a late night on November this past November for Sunday in November when he had an extra hour, because there's actually twenty five hours in that day.

One one am is counted twice. Interesting, isn't that there's a twenty five hour day that we just went through. That's got to mess us up somehow, And it does. The Swedish study I was referring to found that since seven the number of heart attacks rose about five percent during the first week of daylight savings time every year. And then Australia, some Australians looked at some data between nineteen and two thousand one and found that male suicides

increase um in the weeks following daylight savings time. And they're controlling for everything else and it appears to just be daylight savings really affects people with bipolar disorder and they are more men are more prone. Australian men with bipolar disorder are more prone to commit suicide in the weeks immediately preceding the change over to daylight saving. That's

sad It is sad um. There have been some kind of interesting things that happened over the years because of d ST and nine nine the West Bank was on daylight savings. Israel had just switched back to standard time. So a group of West Bank terrorists were preparing some time bombs, smuggled them to their counterparts in Israel, and as they were planning the bombs, they blew up. No, yes, no, it's what it says. Is that from skeptid No is that from Snopes. They'll take snokes too. I think I

think that's real. Wow. I think that happened. Minneapolis and St. Paul were on different, uh, different times in which kind of whack things out am track. A train cannot leave the station before it's scheduled to obviously, can't leave early because everyone's gonna get on. So when you fall back in October, if you're running on time, you stop and sit there for an hour November. What I say October. I think it used to be in October when when

this was written. So you sit there for an extra hour if you're on amtrack on that day, that's right, that's crazy. And then in the spring, apparently they don't do anything but try and catch up, like everything's a little late for a little while, and they just try to like ride faster. Can you imagine being a low logistician. I want to hear from logisticians. I have a deep respect for your profession. Yeah, I agreed, that's tough stuff. Time who knew? You know? Is it arbitrary? What the

clock says? It's just a number. I tend to go with just the rise and fall of the sun and moon. You know, are you kidding me? Like you could throw away every clock in the world and nothing would really change. And you know in uncivilized parts of the world and the civilized world everything runs on the clock. But it's just time. The number was invented by man. I know what you mean. Man, you know what I'm saying, abstract. Thanks for that, Chuck. I think that was an excellent

way to kind of put everybody the sleep. You just put them on a little cloud and went yeah. Man, you know, Um, if you want to learn more about clouds, about daylight savings, time, about Chuck Brian, you can type in those words in any search bar at how stuff works dot com and will bring up some very cool stuff, I assure you. Um, and I said search bar how stuff works dot com. That means it's time Chuck for listeners. That's right, not listener mail. We have a contest we

have nothing to do with. Yeah, this was sprung on us, but we like it. We're in favor of it. Yes, if you are interested in coming to Atlanta, all expense is paid. Yeah, that's the that's the kicker. Actually, I'm not gonna say all expense is paid. Yeah, I don't know if we should legally say that certain expenses are paid. They'll you can come here toward the studio, hang out in the office. We'll even go to lunch with you

with Jerry. Yeah, Jerry will be there and you'll get to see your face like we won't make her wear like a paper bag. You can enter this contest. Uh, it runs now if you're in America. Yeah, yeah, we get in the United States as always saw everyone from Canada and elsewhere that's mad about this. I can't win your contest either. I don't think that makes anybody feel better if you're American, if you're in the United States. It runs through December thirty one. Winners will be announced

the week of January. One grand prize trip to Atlanta includes one night hotel, air fare up to Bucks, and an American Express gift card for incidentals like taking me and check out to lunch. I think we'll pick that up. Uh, And if you refer somebody like you, you go to Facebook the house stuff works dot com not the stuff you should know, go to the house stuff works dot com facebook page to enter and you have to like it and then you enter. But it's the only way

to enter as far as I know. Yeah, I think so. But if you refer someone um and they win, I'm sorry. After person a enters the contest, he or she can share the contest link with friends via Facebook and Twitter, and if a friend of their's winds, then you win a kindle fire. That's not too shabby. Does that make sense? Yeah? And I would. I would give you the link, but

it's like three thousand characters long. So just go to Facebook, how Stuff Work, How Stuff Works dot com, how stuff Works official Facebook page yea, and you will find the information there and lunch, lunch it up with us. Yeah, let's lunch. Let's do lunch before we go. I wanna correct myself big time. Correct myself about patent trolls. In the gene patents Okay episode, I mentioned patent trolls and I don't even remember what I said they were, but

I was way off. Yea. Patentrols are people who go around buying patents with no intent of manufacturing these things or what the patent is for. I figured that's what it was like buying a website domains. Sure, but then they sue. The whole point is to own the patent so that they can sue anybody who infringes on it. So basically they're keeping any kind of innovation from coming about along the same lines of what they own the patent to by suing people who try to do it.

And they're they're basically just whatever, this great idea that's patented is just never going to see the light of day because they have no interest in you and that they just want the money from suing people that's a patentrol. I apologize for to all the patentrols out there. Yes, it's all the people who corrected me. Thank you for that. Yes. Uh. If you want to correct us, we are always up for that. You can send us a tweet at s y ESK podcast. You can join us on Facebook. We

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