Catalytic-converter-equipped vehicles have helped cut other air pollutants by more than 3 billion tons worldwide between 1975 and 2000; of this 1.5 billion short tons was in the United States. Automobiles meet emission standards that required reductions of up to 98+ percent for HC, 96 percent for CO, and 95 percent for NOx compared to the uncontrolled levels of automobiles sold in the 1960s. Despite the fact that fuel use increased approximately 50 percent and vehicle miles traveled nationwide increased by 150 percent between 1970 and 1998, CO, VOC, and NOx emissions from motor vehicles in 1998 decreased by over 44 million short tons