Over 1700 miles this summer, we averaged 2.9 mpg based on gas put in the tank. On my 25 with a Permatrim, efficiency improves with speed. Starting at 12 mph at 2.2 up to 26 mph 2.7mpg. As the speed increases, the trim tabs come up, nearly full down at 12 mph, and full up at 26 mph and motor...