For the first time ever, a gallon of gas will set you back more than $4 in all 50 states. Kansas, Oklahoma, and Georgia were the last to reach the grim milestone, but their prices rose overnight, according to auto club AAA. Averaging $6.02 per gallon, California takes the cake for most expensive gas, and five other states are averaging more than $5 per gallon. High prices at the pump most profoundly affect lower-income families, as they spend a higher proportion of their earnings on gas and are less likely to drive electric vehicles, Mark Finley, a fellow at Rice University’s Baker Institute for Public Policy, told Bloomberg. The price hike comes just before the beginning of peak summer driving season, though a spokesperson for AAA told Bloomberg in an email that it is still too early to know how the higher costs will affect Americans’ driving plans. Gas prices will likely continue rising throughout the summer.