The average fuel economy of 2013 model vehicles sold in the United States through July is 24.7 mpg, up 1.2 mpg compared with 2012 vehicles, according to a monthly report from University of Michigan researchers.
New vans, SUVs, cars and pickups sold in July had an average fuel economy of 24.8 mpg, up 0.1 mpg from June and tying the record high from March, April and May this year, according to researchers Michael Sivak and Brandon Schoettle.
Schoettle, project manager at the university's Transportation Research Institute, said that new-vehicle fuel economy has been fairly stable for several months.
"We feel this is primarily a result of the price of gasoline in the U.S. remaining fairly stable over the same period," Schoettle said in an emailed statement. "These data indicate that demand for fuel efficient vehicles at dealerships remains high -- in addition to recent increases in new-vehicle sales in general."
The average fuel economy of new vehicles sold in July is up 4.7 mpg since October 2007, when the researchers began collecting data.
Schoettle said that he does not expect a large change in the average fuel economy of new vehicles next month unless the price of gasoline changes significantly.
"The trends so far indicate that 2013 [models' average fuel economy] should finish significantly above last year's average," he said. "The average for this year is already 1.2 mpg higher than last year, the largest improvement since the start of our monitoring."
The average sales-weighted fuel economy was calculated using vehicle models' monthly sales and the combined city-highway fuel economy ratings for each model from the EPA Fuel Economy Guide.
The university's national Eco-Driving Index, which calculates the average monthly greenhouse gas emissions from a U.S. driver who bought a new vehicle during the month, dropped to 0.81 in May from 0.82 in April. A lower index score is better, and the scores are compared with a base score of 1 in October 2007, when the researchers began collecting data.