Why do african americans have a higher early puberty rate (50%) than whites (15%)?

Early puberty. I do not believe that the reason is known, although many researchers have studied this situation.
Early Puberty. Good question. Not sure it is entirely correct. We have seen a steady decline in age of menarche is females of all races one the last 2 generations. Thoughts have been it may be related to hormones present in animal food products commonly available such as milk and meat.
Genetics. Its known that african americans begin puberty earlier than other ethnic americans.