SAN DIEGO - The average price of a gallon of self-serve regular gasoline in San Diego County decreased Sunday for the 11th consecutive day, falling six-tenths of a cent to $4.207.

The average price is 6 cents less than one week ago and 13 cents lower than one year ago, but 6.5 cents more than one month ago, according to figures from the AAA and Oil Price Information Service.

Prices had gone up on 28 of the previous 30 days.

The dropping pump prices coincide with a sharp drop in wholesale gasoline prices connected with most California refineries concluding their scheduled maintenance in advance of the switch to sales of summer blend gasoline without major incidents, assuring a satisfactory supply, according to Jeffrey Spring of the Automobile Club of Southern California.