Oh boy, this is an interesting thread . I'm not that fast and just your average hobby runner. Probably the fastest speed I've ever reached in my many full out sprints is equivalent to the average 450-500m world record (right around 19.5 mph).
Marathon: 500m
Half Marathon: 400m
10k: 325m
5k: 300m
1500: 250m
800: 175m
500: 10m
400: Nope.
200: Nope.
100: Nope.
hmm, is this a sign of bad speed endurance?