16-year-old Abdul Hakim Sani Brown (Josai Prep H.S.) ran a world youth lead 20.56 +1.4 for 2nd, making the final. Sani Brown's time put him well ahead of teen sprint sensation Yoshihide Kiryu (Toyo Univ.) on the all-time world youth lists, coming in at #7. And the final is yet to come.
Bolt at age 15 ran 20.58. He's the 15 year old WR holder.
At age 16, Bolt ran 20.13. He's the 16 year old WR holder.
I actually need to remember that stat for the next time I try to counter the argument of "Bolt must be dirty."
Age records website is here: