A new report from the United Nations, titled The State of African Cities 2010: Governance, Inequalities and Urban Land Markets looks at the growth of Africa's urban areas, the fastest growing urban areas in the world. In 2015, the projected urban populations of Lagos (Nigeria) at 12.4 million and Kinshasa (Democratic Republic of the Congo) at 12.7 million will exceed the 12.5 million people of Cairo (Egypt), which is currently Africa's largest urban area.
By 2030 Africa's urban population will be greater than the continent's rural population and by 2050, 60% of all Africans will live in cities. Africa's population crossed the one billion mark in 2009 but the urban population alone will exceed 1.2 billion. Some of the anticipated growth rates for African cities are phenomenal. The report predicts, "Ouagadougou's (Burkina Faso) population is expected to soar by no less than 81 per cent, from 1.9 million in 2010 to 3.4 million in 2020." (Emphasis mine.)

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Sub-Sahara Africa is already in dire straights. Crime rates are astronomical. (In South Africa one third of men admit to having committed rape, frequently of children. Can you imagine?) Millions have AIDS/HIV.
There is already great malnutrition and out right starvation. There is no way these new mega cities can have electric service but for a tiny minority. The people are ill-prepared for development and have the lowest IQs of any population ever tested. Already millions of children die per year from diarrhea when a few drops of laundry bleach in their drinking water would have prevented their deaths.
Over a billion and growing exponentially. The US/Canada/Japan/Europe/Australia, the sustaining countries don’t total a billion.
The population is increasing and food production decreasing, Africa is now Having problems with rural – urban migration, many people are now living in the cities and people no longer want to invest in Agriculture. I predict great famine for the UDC’s in some decades to come.