The average price of gasoline has dropped a penny over the past two weeks to $2.82 a gallon. Industry analyst Trilby Lundberg said Sunday that the current average sits 76 cents below the year-ago price. The cheapest price recorded in the continental United States was $2.33 a gallon in Birmingham. The highest was $4.13 a gallon in Los Angeles. The national average price of diesel was down 6 cents over the same period to $2.86 a gallon.