Gas prices in Maine dropped slightly in the past week, but remain well above the national average. Price-monitoring website MaineGasPrices.com reports Monday that the average retail price in the state fell by just over a penny to $3.58. Nationally, the price remained unchanged, at $3.43 per gallon. Prices in Maine are now nearly 11 cents lower per gallon than a month ago, yet remain more than 18 cents higher than a year ago. A company analyst predicts that prices will fluctuate up and down between now and Christmas.