Despite rising crude prices and a push for more enviro-friendly cars, the average fuel efficiency of American made cars and trucks sold last year has not improved since 2005. The figure has remained at an average of 25.4mpg according to data released from the federal government and published by the Detroit Free Press.

A rise in sales of fuel-thirsty cars have offset increases in the fuel-efficiency of commercial vehicles, and these latest findings are likely to add further pressure on the government to introduce higher efficiency standards. One proposal put forward would force carmakers to increase the average fuel-efficient levels of their fleets by 4% every year until 2017.

This is more evidence of the major carmakers keeping their heads in the sand and not focusing on the problem that lies ahead. The Detroit Three averaged low increases for its cars and trucks, echoed closely by Toyota and Nissan, while average levels Honda fell over the same period. However, most car companies experienced an increase in fuel-efficiency for their passenger car range. DaimlerChrysler was the only full-line carmaker that didn’t see an increase in its efficiency, due mostly to sales of its V8-powered Chrysler 300 models.