Very impressed with gas mileage

I check my gas mileage in my daily driver every tank. I was taught this by my friend's father 30 years ago, as an early indicator of if the engine was out of tune, brakes dragging, tire pressures low etc.

I reset the trip meter on the odometer at the gas station, fill to the 2nd click, and then drive away. Divide the miles by the gallons and bingo.

If I've had one long trip to the city it's usually around 32 mpg. If not, around 25 mpg for that tank of gas.

In reality I'd know there was an issue from the low miles on the trip computer but I still calculate it out anyway.