Fourteen states and the District of Columbia will abide by a deal reached in July by California and four major global automakers to require new vehicles to average approximately 37 miles per gallon by 2026. The Trump administration, meanwhile, is seeking to freeze mileage standards at 2021 levels of only 30 miles per gallon. The four automakers – Ford, Volkswagen, BMW and Honda – comprise about 30 percent of the U.S. auto market.