WASHINGTON, D.C. --- The U.S. average retail price for regular gasoline fell for the fourth straight week last week, dropping 6.1 cents to settle at $3 per gallon, as of Dec. 10. That's 70.7 cents above a year ago, the Energy Department's Energy Information Administration (EIA) reported. All regional prices fell. The East Coast was lower by 4.2 cents to reach $3.031 per gallon. The largest drop occurred in the Midwest, where the price plunged a dime to $2.895 per gallon. The Gulf Coast average price dipped by 5.9 cents to $2.876 per gallon, the lowest regional price. A decline of 4.6 cents in the Rocky Mountain region sent the price to $3.008 per gallon. The West Coast saw the highest regional price in the country --- $3.244 per gallon after losing 3.2 cents. The average price for regular grade in California was $3.329 per gallon, down 3.2 cents from the previous week but 82.5 cents per gallon more than last year. EIA reported that the retail diesel fuel price plummeted 9.1 cents to $3.325 per gallon. Nonetheless, it was 70.4 cents higher than the same week last year. Regional diesel prices were down across the country, with the East Coast price decreasing 7.2 cents to $3.372 per gallon. The Midwest recorded the largest drop, 10.9 cents, to fall to $3.276 per gallon. The Gulf Coast diesel price fell 8 cents to $3.265 per gallon. The Rocky Mountain region's average diesel price slumped 9 cents to $3.397 per gallon. The West Coast price dipped 9.2 cents to hit $3.440 per gallon. California prices plunged 11.2 cents to $3.455 per gallon.