Home Home Home

Vehicle fuel economy drops in December

January 7, 2015

Gas mileage of new vehicles sold in the U.S. slipped last month, according to UMTRI researchers Michael Sivak and Brandon Schoettle.

Average fuel economy (window-sticker values) of cars, light trucks, vans and SUVs purchased in December was 25.1 mpg, down from 25.3 mpg in each of the previous three months and down from an all-time high 25.8 mpg last August. Overall, vehicle fuel economy is up 5.0 mpg from October 2007, the first full month of monitoring by Sivak and Schoettle.

The recent reductions in gas mileage likely reflect the large and continuing decreases in the price of gasoline," Sivak said.

In addition to average fuel economy, Sivak and Schoettle issued a monthly update of their national Eco-Driving Index, which estimates the average monthly emissions generated by an individual U.S. driver. The EDI takes into account both the fuel used per distance driven and the amount of driving—the latter relying on data that are published with a two-month lag.

After setting a record-low 0.76 in August (the lower the value, the better), the EDI regressed for a second straight month to 0.79 in October. The index currently shows emissions of greenhouse gases per driver of newly purchased vehicles are now down 21 percent, overall, since October 2007.