Record high gas prices changing how Americans drive

With wild swings in gas prices pushing ever higher, U.S. drivers are slowly curbing their habits.

Regular-grade gas averaged more than $3.60 a gallon nationwide in 2011 and 2012. It’s never been so high, even when adjusted for inflation. The last records were set during the Iran hostage crisis three decades ago.

High prices, along with recessions, have tugged at America’s driving addiction, bringing down mileage in 1979 and again in recent years. But unlike gas prices, which can arc 40 percent in a year, driving habits die hard.

The difference jumps out when you juxtapose the data in a graphic. Mashing data like this can sometimes be confusing when you have two separate axes, but I think there’s an interesting pattern here.

You can see how gas prices spiked repeatedly over the past 38 years, while driving steadily curved. One’s a puppy bouncing around a room. The other’s a big old dog curled up on a rug, with one eye on the young tyke.

For more of an apples-to-apples comparison, click the “Overall Change” button on the graphic. This shows total growth since 1976. Among telling details: record-high gas prices are just 50 percent higher, while driving has more than doubled.

Click “Rate of Change” for another story. This shows year-over-year changes. You can see just how volatile gas prices have been. But look at the plodding path of driving – the rate of growth has been shrinking.

Of course, many other factors come into play, ranging from gas mileage to economic conditions. But gas prices certainly influence driving.

This data comes from FHWA Highway Statistics 2011 and EIA Short-Term Energy Outlook June 2013, the latest available online.

Preliminary stats for 2012 indicate driving dropped again, but I didn’t include those because they’re in a different FHWA dataset, which gets adjusted. However, I did leave in gas-price estimates through 2014 – they were in the same EIA table.

I imported the data into a Google spreadsheet, along with some calculations done in Excel, and used a Google javascript library to display the results.