Oooh, i love stats! I'm keeping track of the this with Fuelly too. Have been doing it since June 2018, so just under two years (23 months). Here are the stats for my '06 Coupe so far:
Total miles covered: 17,679 miles
Total fuel used: 2,542.39 litres
Total cost of fuel: £3,514.55
Average time between fill ups: 10 days
Average fill up amount: 41.68 litres
Average fill up cost: £57.62 (V-Power 99% of the time)
Average cost per litre: £1.38
Average cost per mile: £0.195
Average miles per gallon: 32.2mpg
Average miles per fuel-up: 289.8 miles
Max amount in one fill up: 50.05 litres

Had a reported 2 miles of range left!
Best MPG: 37.69mpg 8) (40 & 50mph cruising for a few hours with a very steady foot and no stopping or slowing down, still mighty impressive)
Worst MPG: 26.68mpg
The car's my daily driver (well... during normal times) so it does mainly motorway miles during the commute which is reflected in the MPG. Plus i do try to drive as efficiently as possible most of the time. It makes me feel less guilty when i decide to floor it from time to time

. Driving on the motorway at 50-60mph easily return and MPG in the mid 40s. I've found the MPG read-out in the car to be pretty much spot on about 90% of the time which I'm very impressed by. The other 10% of the time it's off by up to 0.5 as mentioned by mmm-five.