The federal government has passed two main laws regulating the efficiency and emissions of motor vehicles nationwide. The Corporate Average Fuel Economy (CAFE) standards, created by the Energy Policy and Conservation Act (EPCA) in 1975 in reaction to the Arab fuel embargo, mandate higher fuel efficiency for vehicles in an effort to reduce U.S. reliance on foreign oil. The Clean Air Act (CAA), passed in 1970, includes a mandate for the regulation of tailpipe emissions of vehicles. The statutory responsibilities for these regulations rest with the National Highway Traffic Safety Administration (NHTSA) and the Environmental Protection Agency (EPA) respectively.