This bit of old news is worth keeping in mind...

In a side-by-side comparison of 2000 census data by sociologist John R. Logan at the Mumford Center, State University of New York at Albany, black immigrants from Africa average the highest educational attainment of any population group in the country, including whites and Asians.

For example, 43.8 percent of African immigrants had achieved a college degree, compared to 42.5 of Asian Americans, 28.9 percent for immigrants from Europe, Russia and Canada, and 23.1 percent of the U.S. population as a whole.

More recent data shows that two out of five foreign-born Africans have a college degree. The ultimate meaning of this information is that poor Africa cannot retain its professionals.