By decreasing gasoline consumption, greater fuel economy could significantly reduce environmental and energy security concerns. In this paper, we show that since the year 2000, technology and market shares have contributed roughly equally to rising new vehicle fuel economy in the United States....

Recent legislation has increased the Corporate Average Fuel Economy (CAFÉ) standard by 40 percent, which represents the first major increase in the standard since its creation in 1975. Previous analysis of the CAFÉ standard has focused on the short run effects, in which vehicle characteristics...