In Africa, mortgages boost an emerging middle class

LUSAKA, Zambia -- Herrick Mpuku has spent a decade building his family a house, and it's still not done. There are no kitchen cabinets, and the concreteblock walls haven't been plastered smooth. But now the 45-year-old economist is having a new home built -- one he expects to go from groundbreaking to the final coat of paint within six months.