(PhysOrg.com) -- Average fuel economy of all new vehicles sold in the United States is up for the second straight month, say researchers at the University of Michigan Transportation Research Institute.
Average fuel economy of cars, light trucks, minivans and SUVs purchased in November was 22.7 mpg, up from 22.6 mpg in October and up from 22.1 mpg in both August and 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 when it was also at 22.7 mpg.
The all-time high of 23 mpg occurred in March of this year. Average fuel economy for new vehicles sold is now 2.3 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 driventhe latter relying on data that are published with a two-month lag.
During September, the EDI stood at 0.87, the highest level since April. The index currently shows that emissions of greenhouse gases per driver of newly purchased vehicles are down 13 percent since late 2007.
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