Depends on the person, in my case i grew up really fast and i was 1.78 with 14-15 years already and never grew a single cm more. My older brother was a midget with 16, he was 1.62 or something, and he ended up with 1.83. You never know man.
22% is 5'8 or shorter? HAHAHHAHA insecure kids lying about their heights even in anonymous vote. That's the average in usa and considering this is a world wide vote the average is something like that probably. We aren't all dutch.