SANTA MONICA, CA - An analysis of the best selling vehicles in 2010 and 2005 reflects a major shift toward fuel efficiency, according to Edmunds.com, an online resource for automotive information.

The top five best-selling vehicle segments generally account for just under two thirds of total vehicle sales. Today’s best sellers earn an average of 20.4 miles per gallon, while the 2005 group earned an average of 18.2 mpg.

“There will come a day in the not-so-distant future when a comparison of fuel efficiency improvements from five years earlier will be laughable,” says Edmunds’ GreenCarAdvisor.com Editor John O’Dell. “There is much promise reflected in the upcoming introductions of mainstream electric vehicles like as the Chevy Volt and the Nissan Leaf.”

In 2005, large trucks were the most popular purchases among new vehicle buyers, and the segment averaged 14.5 miles per gallon. Today, midsize cars sell at the fastest rate and earn an average 22.0 miles per gallon.

The best-selling vehicle segment with the greatest average fuel economy gain over five years is the midsize SUV segment, which improved by 27% and gained 2.2 market share percentage points to boot.