There are two reasons why you might want to consider using the airport restroom before boarding your flight.

The first reason benefits you: Who wants to compete with an entire airplane cabin to use the lavatory? If the seatbelt sign is on, you’ll have to wait even longer.

If you’re sitting in a window seat, you have to climb over other passengers to get out. If you’re in an aisle seat, they’re climbing over you.

And the second reason not to use the lavatory benefits the airlines is that the latest research shows that if only half the passengers who wanted to use the lavatory did so before boarding, the weight reduction on board and the lower fuel consumption per flight, could save the airline nearly $1,000,000 a year per plane.