The SAFE vehicle rule rolls back stricter fuel efficiency standards of the Obama administration. The SAFE rule requires manufacturers to improve the fuel efficiency of their light duty vehicles by 1.5% year-to-year from model year 2021 to 2026, reaching 40 miles per gallon by 2025. Obama administration standards would have required a roughly 5% annual increase, reaching 54 miles per gallon by 2025. Several states are pushing back against the rollback with legal challenges.