My almost 4.5 year old car just hit 7,100 miles (~11,426 kilometers).
My last tank of gas I averaged 44 miles per gallon by the time it was down to about a quarter tank, my usual refill point.
Right now, at about 7/16ths of a tank, I'm at 48mpg.
That got skewed upwards when I had my battery replaced (South Florida heat) which, for some reason, added about 6mpg from where it was literally 15 minutes before.
I'd hit 44mpg once before, so I guess that's more accurate.