Driving the furious potato (our 6mo baby boy) up and down a quiet dual carriageway for an hour to get him to sleep. ACC on, 55mph, flat road, light wind, no traffic and still only 65.2mpg against a combined book figure of 65.7mpg (extra urban of 72.4mpg!?!)
Little bit surprised how far short of the book figures it still is as my car is presumably well run in by now.
Still, first world problems etc.