i dont believe you !
What proof do your offer that your old car could achieve 72 miles on each gallon of gasoline?
Did you use math or "I went all the way to Joey's 3 hours away on just one tank" and estimated that you got 72 mpg ?!?!?!??!?!
Too many of the the people I know, when we start talking cars, use the "I drove all day on 3/4 of a tank" method to brag about their great mileage and dont even know how to accurately divide by the gallons pumped to top the tank into the miles driven AFTER topping the tank at the start of the test.
Oh well. whatever you say