Nigeria's Buhari still against naira devaluation, says has not previously helped

President Muhammadu Buhari said on Friday he is yet to be convinced that Nigeria would benefit from a devaluation of the naira, despite its sharp fall against the dollar on the black market and rising inflation. The slump in global crude prices has caused the worst economic crisis in years in Nigeria, Africa's top oil exporter, as oil sales account for about 70 percent of national income. The official exchange rate against the dollar was pegged at 197 in February last year but a foreign exchange