The average price of a gallon of regular gasoline nationwide dropped in the past week.  Gas was at $1.93 per gallon, down from $1.99, while it was at $2.10 per gallon one year ago.  There was a nice decrease in Illinois for the past week, as it dropped from $2.01 per gallon of regular to $1.92.  It dropped significantly in Nashville from $1.79 per gallon of regular gas to $1.69 in the past week.