WASHINGTON, D.C. --- The U.S. average retail price for regular gasoline fell 11.9 cents last week to hit $2.378 per gallon as of Sept. 25, the Energy Department's Energy Information Administration (EIA) reported. That's 42.5 cents lower than the average price from a year ago. East Coast prices fell 14.4 cents to $2.384 per gallon, while Midwest prices fell 11.2 cents to $2.207 per gallon. West Coast prices were still the highest in the nation after falling 8.8 cents to $2.718 per gallon, the lowest price in that region since April 3. California prices were also 8.8 cents lower at $2.760 per gallon, which is 18.7 cents lower than this time last year. Retail diesel fuel prices fell by 11.8 cents to reach $2.595 per gallon as of Sept. 25, 20.3 cents lower than last year. This is the sixth week in a row that diesel prices have fallen, the EIA said. Diesel prices dipped throughout the country, with the Rocky Mountains seeing the largest regional decrease of 22.5 cents to $2.827 per gallon. West Coast prices, the highest regional prices in the country, averaged 12.2 cents lower to hit $2.892 per gallon. This is the first time the price has been below the $3 mark since April 17.