Fitch Ratings Ltd. revised the outlook on Nigeria to negative from stable over concerns that a lack of foreign exchange will hamper the economy, and affirmed the West African nation’s rating at B+, four steps below investment grade. While Nigeria’s economy will probably expand at 1.5 percent this year, after contracting by an estimated 1.5 percent in 2016, the non-oil industry will continue to be constrained by foreign-currency shortages, the ratings company said in an e-mailed statement on Wednesday. “Access to foreign exchange will remain severely restricted until the Central Bank of Nigeria can establish the credibility of the interbank foreign-exchange market and bring down the spread between the official rate and the parallel market rates,” Fitch said. The central bank removed a currency peg in June but continued to intervene to keep the naira at about 315 against the U.S. dollar, compared with almost 500 on the parallel […]