ANN ARBOR—Gas mileage of new vehicles sold in the U.S. stayed the same last month, according to researchers at the University of Michigan Transportation Research Institute.

Average fuel economy (window-sticker values) of cars, light trucks, vans and SUVs purchased in November was 25.3 mpg, the same as both September and October, but down from 25.8 mpg in August. Vehicle fuel economy is up 5.2 mpg from October 2007, the first full month of monitoring by UMTRI researchers Michael Sivak and Brandon Schoettle.

“The unchanged average fuel economy is likely a net consequence of two opposing trends—less demand for more fuel-efficient vehicles because of the decreasing price of gasoline, and improved fuel economy of 2015 model year vehicles compared to 2014 model year vehicles,” 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 four months of improvement, the EDI fell back to 0.78 in September from August’s record-low 0.76 (the lower the value, the better). The index currently shows emissions of greenhouse gases per driver of newly purchased vehicles are now down 22 percent, overall, since October 2007.

Related Links:

• Fuel economy (with graph and table of current/recent mpg): http://bit.ly/1ugjpww
• Eco-Driving Index (with graph and table of current/recent values): http://bit.ly/1yrueet
• Michael Sivak: http://bit.ly/HZlMiS
• Brandon Schoettle: http://bit.ly/1pGoBDl

U-M Sustainability fosters a more sustainable world through collaborations across campus and beyond aimed at educating students, generating new knowledge, and minimizing our environmental footprint. Learn more at sustainability.umich.edu.