Pointing put averages is useless without attempting to understand why those averages exist.

Read/ listen to Thomas Sowell talking about the issue, in particular African geography.

Combine that with aggressive democrat policies aimed at destroying the black family; add in government policy to distribute heroin in the 70s and crack in the 80s. Throw in CIA created gangster rap, and we start to see why.

Second generation Nigerian and Jamaican immigrants in the US on average outperform white people in the US.

Culture is the culprit, not genetics. Same reason the average white American is retarded in comparison to the average white European or Australian.