CULVER CITY, Calif. (AP) - Californians may be paying the highest gasoline taxes in the nation when a 3 ½-cents-per-gallon increase kicks in this summer.

The state Board of Equalization on Thursday voted to hike the excise tax to 39.5 cents per gallon. The board is required each year to adjust that tax to maintain a certain level of revenue based in part on gas prices and consumption - and consumption's been falling.

The excise tax is levied on gasoline suppliers but it's often passed on to consumers.

Coupled with federal and other state taxes, drivers may be paying more than 70 cents in taxes for every gallon.

Californians already pay some of the nation's highest pump prices. The average price of regular on Friday was more than $4.23 per gallon.

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