Africa throwing away dollars it cannot afford in currency rout

Lagos

AFRICA is battling the global currency markets with one hand tied behind its back. With foreign-exchange reserves equal to less than a 10th of the emerging-market average, nations from Ghana to Zambia are finding they are powerless to stop their currencies from tumbling amid a rout in commodities, China's devaluation and the prospect of higher interest rates in the United States.

Half the 10 worst-performing currencies this year are from Africa, even though policymakers are burning through their reserves faster than any other region. "African central banks are being pushed to the brink," said Nema Ramkhelawan-Bhana, an economist in Johann…