I buy fuel in bulk, store it in one tank, and fill my company vehicles from the bulk tank. How do I determine the gasoline expense per vehicle on the TurboTax vehicle expense worksheet. I use actual expenses per vehicle instead of mileage.

I buy fuel in bulk, store it in one tank, and fill my company vehicles from the bulk tank. How do I determine the gasoline expense per vehicle on the TurboTax vehicle expense worksheet. I use actual expenses per vehicle instead of mileage.