The Federal Reserve probably needs to keep U.S. interest rates lower for longer given headwinds from weak global economic growth, a stronger dollar and an unexpectedly sustained drop in oil prices, a top Fed official suggested on Friday. San Francisco Federal Reserve Bank President John Williams told reporters he now sees slightly slower growth, slightly higher unemployment, and about a tenth of a percent lower inflation this year than he had expected in December, when the Fed raised rates for the first time in nearly a decade. At the time, officials at the Fed, the U.S. central bank, had as a group expected about ... (full story)