ANN ARBOR—Gas mileage of new vehicles sold in the U.S. remained unchanged 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 July was 25.4 mpg.

“The fuel economy in July was unchanged from that in June, consistent with the increased market share of vehicle in the middle of the fuel-economy spectrum, such as crossovers,” said Michael Sivak, a research professor at UMTRI.

Overall, fuel economy is down 0.4 mpg from the peak reached in August 2014, but up 5.3 mpg from October 2007—the first full month of monitoring by Sivak and colleague Brandon Schoettle.

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.

During May, the EDI improved to 0.82 (the lower the value, the better) from 0.85 in April. The index currently shows emissions of greenhouse gases per driver of newly purchased vehicles are down 18 percent, overall, since October 2007. EDI reached its best level (0.78) in August 2014.

More information:

• Fuel economy 
• Eco-Driving Index
• Michael Sivak
• Brandon Schoettle

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.