According to a monthly report by Michael Sivak and Brandon Schoettle from the University of Michigan, the average fuel economy of newly purchased vehicles hit a new record high during the month of August.

The average fuel-economy (window-sticker) value of new vehicles sold in the U.S. in August reached a new record high--24.9 mpg. This value is up 0.1 mpg from July and up 4.8 mpg since October 2007 (the first month of our monitoring). For a description of the calculations and the recent mpg values, click here.

The average fuel economy of model year 2013 vehicles sold thus far (October 2012 through August 2013) is 24.7 mpg. This is up 1.2 mpg from model year 2012 vehicles.

The University of Michigan Eco-Driving Index (EDI)--an index that estimates the average monthly emissions of greenhouse gases generated by an individual U.S. driver--stood at 0.81 in June (the lower the value the better). This value indicates an improvement of 19% since October 2007. 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). Click here for a brief description of what the EDI is, how it is calculated, and the current and recent values of the EDI.

According to GasBuddy, the national average in August was 23-cents per gallon higher than it was in July, which may contribute to the increase in fuel economy of new vehicles. Americans tend to buy more fuel efficient vehicles when gasoline prices are rising. The average pump price in August according to GasBuddy was $3.69 per gallon, while prices in July averaged $3.45 per gallon.