BOSTON— The average cost of a gallon of gasoline in Massachusetts is down 4 cents this week.

AAA Northeast's weekly price survey release Monday found self-serve, regular selling for an average of $2.71 per gallon. The Massachusetts price is 3 cents lower than the national average and 18 cents lower than the in-state average price a year ago.

AAA spokeswoman Mary Maguire says prices are dropping due to cheaper crude oil while at the same time U.S. supply is keeping pace with demand.

AAA found self-serve regular selling for as low as $2.53 per gallon and as high as $3.05.

On Cape Ann, prices for a gallon of regular gasoline ranged from $2.87 to $2.99 on Monday, according to GasBuddy.com.

Material from the Associated Press was used in this report.