Trip from Quebec City to NJ
Miles travelled on one tank: 500
Amount of fuel replaced at fill up in NJ: 21.3 gallons
OBC mileage: 23.7 mpg
Observed (500/21.3): 23.4mpg
Speed: On average over 70mph since more familiar with the cop situation
Air conditioner on/off: ON

Out of interest, does Canadian Octane 91 gas have 10% Ethanol? Filling up a tank in Quebec City costs $1.44*80. Costs around $70 in NJ