As said, driving a mile is your problem - you know what the Clio's like when it first starts? It's chucking petrol in there to keep it from stalling, it hasn't got up to optimum temperature yet.
My drive to work used to be a round trip of 35miles and I'd get an average of 35mpg minimum, and that's with some spirited driving! I could go 11 days without having to fill up
On long journeys if I want to be anal enough, I can get it to nudge 50mpg, but I've seen to get it well below 30mpg before too. Everything depends on how you drive, the conditions and also very importantly, for how long.