The average price of a gallon of regular gasoline nationwide dropped slightly in the past week, as it was at $2.40 per gallon, but dropped to $2.39, while it was at $3.60 per gallon one year ago.  There was a significant decrease in Illinois for the past week, as it went down from $2.60 per gallon of regular gas to $2.54 this past week.  It went down in Nashville this past week also, being near $2.35 per gallon from $2.39 the previous week.