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Believe it or not, there is a downside to cheap gas, even for consumers. There's a way low prices can end up being very costly. To explain, NPR's Shankar Vedantam talked to our own David Greene.
DAVID GREENE, BYLINE: So when I see gas prices tumbling at gas stations, I usually feel really good about that. You're saying that there's some problems here?
SHANKAR VEDANTAM, BYLINE: Well, I feel really good about it, too, David. But it turns out that cheaper gas does come with a downside. And the downside is more traffic crashes and more traffic fatalities. I came by this analysis of the relationship between gasoline prices and road fatalities in 144 countries. And what it finds is that higher gas prices are associated with fewer fatalities. Lower gas prices are associated with a larger number of traffic deaths.
I spoke with Guangqing Chi. He's a sociologist at South Dakota State University. He's been analyzing the relationship between gas prices and road fatalities in the United States. He told me about one study he conducted that found that a 20-cent decline in gas prices in Minnesota was linked to an additional 15 deaths per year. I asked him what the effect of a $2 drop in gas prices might be across the entire United States. Here he is.
GUANGQING CHI: A $2 drop in gasoline price can translate to about 9,000 road fatalities per year in the U.S.
GREENE: Nine-thousand? Shankar, I mean, I know we haven't seen a $2 drop in gas prices in the country. But he's estimating that a drop like that could cause an additional 9,000 road deaths? That really scary.
VEDANTAM: It is scary, David. My jaw dropped when I heard that number. Now, even if we take a more conservative estimate than Chi - let's say a third of his estimate - that's still 3,000 lives a year. It's an enormous number of people.
GREENE: So, Shankar, why is this happening?
VEDANTAM: Well, the biggest factor of course, David, is that people simply drive a lot less when gas prices are high. Chi told me that he himself started this line of research when gas prices spiked in 2008, and he noticed a change in his own behavior. Instead of taking a lot of separate trips to home and shopping and to pick up his kid, he would start to combine all these trips into one trip. Here he is.
CHI: In the past, when the gasoline price is not that high, I go to office. I go home. I go shopping. I go home. I pick up my kid from day care. Then I go home. But now, with the gasoline price so high, I try to do all the things together - just do it in one trip.
VEDANTAM: And, you know, David, he also noticed that he started to drive differently when gas prices were high. He would accelerate slowly, maintain a steady speed - because those are the things that save gas. But it also turns out those are the things that make you safer driver.
GREENE: That's amazing. So you're not actually doing things to be a safer driver. But the things you're doing to save gas are actually making you a safer driver without you even realizing it.
VEDANTAM: You know, the ironic thing, David, is that if you really want to get people to slow down, you don't scare them about losing their lives. You scare them by telling them they're going to spend more money at the pump. And that's what gets them to slow down.
GREENE: Wow. And when you're talking about who to send a message like that to - I can imagine this is a problem that affects different people differently. I mean, if you're a younger driver, you have maybe less disposable income. You might actually change your behavior more.
VEDANTAM: That's exactly right. Chi actually finds that the risk for teenagers goes up very sharply when gas prices fall, presumably because these drivers in their teens and early 20s are likely to drive a lot less when gas costs more. Now of course, these are also drivers who are often higher-risk drivers to begin with, so when you get them off the road, that lowers the risk for everyone else as well.
GREENE: Shankar, this strikes me as a big deal. I mean, is there something that government officials should be thinking about doing to raise awareness of this problem?
VEDANTAM: Well, David, the obvious answer is that higher gas prices are probably going to save lives. Chi himself thinks that we should maybe impose gasoline taxes, raise the price of gasoline - and that would not make consumers happy - but it probably would save lives.
The complicated thing, of course, David, is that higher gas prices are also a break on the economy. And they disproportionately affect poorer people because wealthier people are likely to drive regardless of whether gas prices are high or low. As far as individual drivers go, David, I think the thing to do is that if you see a sign showing low gas, the thing to do is to check your seatbelt and make sure you're staying alert on the roads.
GREENE: Something you should always be doing anyway.
GREENE: Shankar, thanks as always.
VEDANTAM: Thank you, David.
GREENE: We've been speaking to our colleague Shankar Vedantam, who regularly joins us on this program to talk about social science research. And you can follow him on Twitter @hiddenbrain. You can also follow this program @NPRGreene, @NPRInskeep and @MorningEdition. Transcript provided by NPR, Copyright NPR.