This report summarizes key fuel economy and technology usage trends related to modelyear (MY) 1975 through 2006 light-duty vehicles sold in the United States. Light-duty vehiclesare those vehicles that EPA classifies as cars or light-duty trucks (sport utility vehicles, vans, and pickup trucks with less than 8500 pounds gross vehicle weight ratings). Since 1975, the fuel economy of the combined car and light truck fleet has moved through four phases: (1) a rapid increase from 1975 continuing to the mid-1980s, (2) a slow increase extending into the late-1980s, (3) a gradual decline until the mid-1990s, and (4) a period of relatively constant fuel economy since then. MY2006 light-duty vehicles are estimated to average 21.0 miles per gallon (mpg). This average is the same as last year and in the middle of the 20.6 to 21.4 mpg range that has occurredfor the past fifteen years, and five percent below the 1987 to 1988 peak of 22.1 mpg. After over two decades of steady growth, the market share for light trucks has been about half of the overall light-duty vehicle market since 2002. Most of this growth in the light truck market has been led by the increase in the popularity of sport utility vehicles (SUVs), which now account for more than one-fourth of all new light-duty vehicles. MY2006 light-duty vehicles are estimated, on average, to be the heaviest, fastest and most powerful vehicles than in any year since EPA began compiling such data. The fuel economy values in this report are based on real world estimates provided by the Federal government to consumers and are about 15 percent lower than the values used by manufacturers and the Department of Transportation (DOT) for compliance with the Corporate Average Fuel Economy (CAFE) program. Because it has been over two decades since the current procedures for determining real world fuel economy estimates were established and because both vehicle technology and vehicle driving patterns have changed, EPA has proposed changes
to the methodology for calculating real world fuel economy estimates and expects to finalize a new methodology by the end of 2006.