	nigeria changes auction rules to defend naira nigeria s central bank has changed the rules governing its foreign exchange auctions in what analysts see as a means of defending the naira currency which has depreciated steadily the bank said in a statement that from april banks bidding for foreign exchange would have to pay at the rate they offered and not as presently at the rate of the lowest successful bid made at the auction this should discourage banks from bidding high to ensure that they were successful while paying the lower marginal rate analysts said the central bank also announced the auctions would be fortnightly not weekly beginning on april reuter 
