The intention of the Nigerian authorities is to discourage speculation against the naira, something that has added to the pulls of falling oil prices and a strengthening dollar. But the result has been a dramatic widening between the official and unofficial foreign exchange rates.
Before November, Nigeria’s currency resisted remarkably well the drop in the oil price that started last summer. Throughout the first 10 months of 2008 the naira remained relatively stable at about 117 to the dollar. But between November and mid-January, the currency fell by more than a...
