For the first time since late December the price of gasoline has gone down. The Lundberg Survey says the national average is down six cents per gallon over the last two weeks. The price of a gallon of regular is $3.74. Diesel was down four cents to $4.13 gallon. Of the cities surveyed in the lower 48 states, Billings has the nation's lowest average price for gas at $3.31. Los Angeles has the highest at $4.23. The lowest price in Missoula is $3.22.