DETROIT -- New cars and trucks for sale on U.S. dealer lots today get nearly 3 mpg more than new vehicles for sale four years ago, University of Michigan researchers said.
For all 2012 light vehicles offered for sale, the average EPA estimated fuel economy is 21.5 mpg, up 14 percent from 18.9 mpg for 2008 models, according to the report from the university's Transportation Research Institute.
The study covers new vehicles offered for sale -- but not necessarily sold -- by dealers in the United States.
As for sold light vehicles, the average fuel economy rose 1.7 mpg from 2008 models (20.8 mpg) to 2011 models (22.5 mpg) -- the last full year for which sales are available. The analysis of sold vehicles did not include 2012 models because only three months of sales were available, according to the study.
The institute used EPA data and examined fuel economy changes by vehicle characteristics, class size, transmission type, number of engine cylinders, drive type and fuel type. It also examined hybrid vehicles vs. gasoline-powered vehicles.
In the class size category, station wagons had the largest increase among vehicles for sale, rising 4.1 mpg from the 2008 (21.9 mpg) to 2012 (26 mpg) model years. Full-sized vans had the smallest increase, only 0.2 mpg, from 13.2 mpg in 2008 to 13.4 mpg in 2012.
On average over the period, compact cars' fuel economy improved 3.8 mpg to 25.6 mpg. Small pickups improved 0.4 mpg to 18.6 mpg, the report said.
Among engine types, diesel engines improved 9.8 mpg while conventional gasoline engines improved only 2.6 mpg over the period.