(PhysOrg.com) -- For the first time in seven months, average fuel economy of all new vehicles sold in the United States is on the rise, say researchers at the University of Michigan Transportation Research Institute.
Average fuel economy of cars, light trucks, minivans and SUVs purchased in October was 22.6 mpg, up from 22.1 mpg in September.
According to Michael Sivak, research professor and head of UMTRI's Human Factors Group, average fuel economy of all new vehicles bought last month is at its highest level since May and registered its first increase since March---when it hit an all-time high of 23 mpg.
"The increase is likely a consequence, in part, of the improved fuel economy of model year 2012 vehicles, which were introduced this fall," Sivak said.
Average fuel economy for new vehicles sold is now 2.5 mpg better than just four years ago.
In addition to average fuel economy, Sivak and UMTRI colleague Brandon Schoettle issued their monthly update of their new national Eco-Driving Index, which estimates the average monthly environmental impact of an individual U.S. driver. The EDI takes into account both vehicle fuel economy and distance driven---the latter relying on data that are published with a two-month lag.
For a third straight month (August), the EDI stood at 0.86. The index currently shows that emissions of greenhouse gases per driver of newly purchased vehicles are down 14 percent since late 2007.
Explore further: Fuel economy of new vehicles still at lowest point in the past year