Black inferiority is still being studied BgMc, although I'm not sure why. But on average, African-Americans 15 points lower than European-Americans on IQ tests depending on age.
http://www.scienceblog.com/cms/node/7669
"Around the world, the average IQ for East Asians centers around 106; for Whites, about 100; and for Blacks about 85 in the U.S. and 70 in sub-Saharan Africa."
Forest Gump was only 3 point bellow 70 if you remember the movie.
"Black children sit, crawl, walk, and put on their clothes earlier than Whites or East Asians."
intesting that black people start off ahead of the curve then other races pass them by.
"Black children with lighter skin, for example, average higher IQ scores. "