Nigeria, March 3 -- There was always something wide off the mark with the idea of restricting the interest rates banks pay on savings account deposits. The Central Bank of Nigeria (CBN) currently has this cap at about a third of its Monetary Policy Rate (MPR). As with all attempts at price control, one outcome of this policy is the proliferation of perverse responses. Predictably, one suggestion is that only a few banks in the country pay interest rates on savings deposits at more than 5 per cent per annum - way below the CBN's "recommended retail price" for savings account. This is interesting in several respects because given an MPR rate of 27.5 per cent, the yield on savings accounts (indicated by the cap) should be at least 9 per cent...