Gas prices are falling again in the St. Louis area, down 8.1 cents per gallon in the past week. That's according to GasBuddy.com. The average gallon of gas is now going for $3.73 in St. Louis. This compares with the national average that has increased 3.2 cents per gallon in the last week to $3.68/g. The price of gas yesterday was 32.9 cents per gallon higher than on the same day last year.