WASHINGTON, D.C. --- After six weeks of decline, the U.S. average retail price for regular gasoline jumped 7.3 cents to reach $3.053 per gallon as of December 31. That's 71.9 cents above a year ago, the Energy Department's Energy Information Administration (EIA) reported last week. Prices increased in all regions of the nation except the Rocky Mountains, where the price fell 0.7 cent to $2.921 per gallon. The East Coast price rose 5.8 cents to $3.065 per gallon. The largest increase, 11.4 cents, occurred in the Midwest with the price stopping at $3.032 per gallon, the EIA said. The Gulf Coast price swelled by 8.4 cents to $2.920 per gallon, still the lowest regional price. The West Coast maintained the highest regional price, rising 3.6 cents to $3.218 per gallon. The average price for regular grade in California climbed to $3.298 per gallon --- 3.7 cents more than the previous week and 68.8 cents per gallon more than the same week last year. Rising for the first time since late November, the retail diesel fuel price grew to $3.345 per gallon, 3.7 cents over a week earlier and 76.5 cents higher than last year. Regional diesel prices were higher throughout the country, with the East Coast price climbing 4.3 cents to reach $3.399 per gallon. The Midwest diesel price rose 3.2 cents to $3.309 per gallon. The Gulf Coast diesel price tallied the largest regional increase, rising by 4.7 cents to $3.293 per gallon. The Rocky Mountain diesel price edged up 0.1 cent to $3.269 per gallon, representing the lowest regional price. The West Coast diesel price increased 4.0 cents to $3.451 per gallon. California diesel prices were up 5.7 cents to $3.491 cents per gallon, the EIA said.