I saw the headline and immediately guessed it would be African born blacks. The qualification that must be made though is that, like most overseas immigrants, we tend to get their best and brightest while their lesser brothers are stuck in the homeland.
Immigrants from SE Asia, India and Africa that aren’t here as refugees (Somalis) get here because they have shown ambition, talent, and intelligence to get the education and skills we want. Naturally they will outperform most other demographic groups.
Most don’t understand that distinction between immigrant and refugee. The ungrateful, undeserving “Go Back” Omar is an example.