That works out (theoretically) at about 35mpg. (Corsa fuel tanks hold about 44-45 litres). That would be the figure if you really used a full tank (i.e. if you actually carried on driving until you ran out of fuel). In practice, you probably left some fuel in the tank, so the figure might be nearer to 38mpg.
Personally, for a 1 litre engine, I'd regard that figure as rather lower than I'd expect. My ancient 1.3 litre Proton usually gives me between 36 and 40mpg and I don't regard that as particularly efficient.
If your driving was largely urban, then I'd have to agree that your fuel consumption was quite good. (The manufacturer's urban cycle figure is around 41mpg, so if you get only just below that theoretical figure, you're doing quite well). However, the manufacturer's figure for 'combined' driving conditions is 53mpg. In real life conditions I'd hope to achieve 40-45mpg. The extra-urban figure is 64mpg. In real life conditions, prolonged motorway driving should give you around 50mpg.
Chris