It might depend on the car. Or even for a given car, when you drive at 55 miles per hour, there's some variation in your gas mileage. It might be how recent an oil change happened, what the wind conditions are like, what the road conditions are like, I mean, exactly how you're driving the car. Are you turning? Are you going in a straight line? And same thing for 70 miles an hour. So when we're seeing in general, there's variation in what the gas mileage is at 55 miles an hour and at 70 miles an hour.