Changes in travel closely linked to percentage shifts in fuel prices

When you notice gas prices starting to creep higher, you might consider a number of significant changes to your driving habits. Perhaps you'll reign in your vacation plans, consider a more efficient model for your next vehicle, or check with your co-workers to see if anyone wants to start a carpool. You might also make smaller adjustments without really thinking about it, such as consolidating trips instead of making multiple drives for different errands.

An analysis by the Office of Energy Efficiency and Renewable Energy suggests that such habits result in fairly routine changes in travel based on gas prices. In analyzing a decade of data on fuel prices and travel, the office—part of the Department of Energy— determined that changes in travel are closely associated with the percentage change in gas prices. Sudden spikes in gas prices had less of an effect on travel, but prolonged adjustments in travel costs were more likely to result in increased or decreased travel.

The analysis charts changes between January 2008 and December 2017, looking at how the change in gas prices from the previous year correlated to a change in travel. For example, a year-over-year increase of gas prices by more than 30 percent in the summer of 2008 was associated with a travel reduction of nearly 5 percent. A year later, when gas prices were about 40 percent lower than the previous year, travel was up by just over 3 percent.

Similar shifts occurred in 2011 and 2015, which saw an uptick in gas prices as well as a downward trend in fuel costs, respectively. In the summer of 2011, travel fell by more than 3 percent compared to the previous year as gas prices were up by more than 30 percent. A yearover-year reduction in gas prices by over 30 percent in January 2015 led to a travel increase of about 4 percent.

The Office of Energy Efficiency and Renewable Energy cautioned that other factors also affect how many miles drivers travel at any given time. These include economic conditions, driver licensing rates, demographics, and infrastructure conditions.

Other studies have suggested that drivers begin to adjust their driving habits once gas prices reach a certain point. A 2013 AAA survey of 1,011 adults determined that the median respondent considered $3.64 to be too much to pay for a gallon of gas. Sixty-two percent said they would change their driving habits if gas got too expensive, with 86 percent of those who made adjustments saying that they drove less frequently.

A year later, however, a similar survey by AAA found that drivers were less likely to change their driving habits despite higher prices. Fifty-three percent said they would make changes, with 85 percent of those saying they would combine trips or errands and 84 percent saying they would drive less often.

Fuel economy also tends to be a less pressing consideration for new vehicle buyers when prices at the pump are low. A 2017 study by the market research firm MaritzCX found that consumers began citing fuel economy as a more important issue in their vehicle choice once prices reached $3 a gallon or higher.