South Africa has also been a purchaser of electric current from Mozambiques Cabora Bassa hydroelectric power dam. South Africa is a major supplier of refined oil to five of her neighbors. South Africa has substantial ongoing capital investments in all of the southern African countries except Angola and Tanzania. An estimated 200.000 migrant workers from all of the neighboring countries except Zambia are wageearners in the South African business community. South Africa is the major supplier of aid funds to southern Africa. According to the recent study of South Africa by the Foreign Policy Study Foundation. which was funded by the Rockefeller Foundation.