Just call me lead foot.
I am always well under and even on motorway journeys don't exceed the listed figure.
The MB ML63 is listed as 23.9 but my trip computer shows 18.2. The day I bought it and came home I deliberately went as gentle as possible (Essex to Whitchurch on the motorway out of rush hour) and got 22.1 which is the highest I ever recorded.
My last E63/212 was meant to be 24.8 and I got 19.8 over 22k miles with a peak of 24.2 on a long run to scotland at the legal ilmit.
SWMBO Mini CooperS was meant to be 44 but usually shows 32-35. I don't think it is actually possible to drive it without ragging it!
I like the figures on the honest John site -
https://www.honestjohn.co.uk/realmpg/mini/cooper-and-s-r56-2007I have never had a car that gets close to the average, leadfoot.