Cars and light trucks are considered separately for CAFE and are held to different standards. As of early 2004, the average for cars must exceed 27.5 mpg, and the light truck average must exceed 20.7 mpg. Trucks under 8500 pounds must average 22.5 mpg in 2008, 23.1 mpg in 2009, and 23.5 mpg in 2010. After this, new rules set varying targets based on truck size "footprint."
In late 2007, CAFE standards received their first overhaul in more than 30 years. On December 19, President Bush signed into law the Energy Independence and Security Act of 2007, which requires in part that automakers boost fleetwide gas mileage to 35 mpg by the year 2020. This requirement applies to all passenger automobiles, including "light trucks." Politicians had faced increased public pressure to raise CAFE standards; a July 2007 poll conducted in 30 congressional districts in seven states revealed 84-90% in favor of legislating mandatory increases.[23]
Overall fuel economy for both cars and light trucks in the U.S. market reached its highest level in 1987, when manufacturers managed 26.2 mpg (8.98 L/100*km). The average in 2004 was 24.6 mpg.[22] In that time, vehicles increased in size from an average of 3,220 pounds to 4,066 pounds (1,461*kg to 1,844*kg), in part due to an increase in truck ownership during that time from 28% to 53%.
A number of manufacturers choose to pay CAFE penalties rather than attempt to comply with the regulations. As of model year 2006, BMW, DaimlerChrysler, Volkswagen, Ferrari, Porsche and Maserati failed to meet CAFE requirements.[24]
For the 2008 model year, Mercedes-Benz had the lowest fleet average while Lotus had the highest.[25]