The average price of a gallon of self-serve regular gasoline in San Diego County rose four-tenths of a cent Friday to $4.779, its highest amount since May 28. The average price is 3.5 cents more than one week ago, 23.3 cents more than one month ago and 8.8 cents more than one year ago, according to figures from the AAA and the Oil Price Information Service. The national average price decreased four-tenths of a cent to $3.199. It is 1.1 cents more than one week ago and 6.9 cents more than one month ago, but 2.5 cents less than one year ago. The national average price has dropped $1.817 since rising to a record $5.016 on June 14, 2022.