Automaker rankings 2007

"Automaker Rankings 2007: The Environmental Performance of Car Companies" analyzes the bottom-line environmental performance of eight companies, which together account for 96 percent of cars and trucks sold in the United States -- the world's largest vehicle market. The analysis uses sales and emissions data from the U.S. Environmental Protection Agency and Department of Transportation for model year 2005. Overall scores are based on a 50/50 weighting of average per-mile emissions of smog-forming and global warming pollutants from each manufacturer's vehicles. The average across all eight automakers is defined as a score of 100 and lower scores indicate less pollution.