WASHINGTON, D.C. --- The U.S. average retail price for regular gasoline fell 1.8 cents to hit $2.208 per gallon as of Oct. 23. That's 39.5 cents lower than a year ago, the Energy Department's Energy Information Administration (EIA) reported. East Coast prices fell 2.8 cents to $2.179 per gallon, 45.6 cents lower than at this time last year. The Midwest saw a rise of 1.8 cents to $2.147 per gallon, but the price is still 30.4 cents lower than at this time last year. The Rocky Mountains' average price fell 6.2 cents to $2.352 per gallon, while West Coast prices fell 5.0 cents to $2.459 per gallon. California prices fell by 5.9 cents to $2.481 per gallon, the EIA reported. Retail diesel fuel prices saw their first increase in 10 weeks, with prices rising 2.1 cents to $2.524 per gallon. East Coast prices were up 1.6 cents to $2.537 per gallon, and Midwest prices rose 4.3 cents to $2.502 per gallon. The Gulf Coast saw the average diesel price rise by 1.6 cents to $2.477 per gallon, while the Rocky Mountains saw a 2.4-cent jump to $2.563 per gallon, the EIA said. The West Coast was the only region where diesel prices fell, with a 2.7-cent decrease to $2.628, which is 51.4 cents per gallon lower than at this time last year.