Wall Street set to open lower on Fed warning, Brexit vote

Wall Street was set to open lower on Thursday, a day after the Federal Reserve's warning about an economic slowdown added to concerns of Britain's possible exit from the European Union. The Fed said it continued to expect two hikes this year but the consensus seemed shakier with six of the 17 policymakers projecting just one hike. Fed Chair Janet Yellen sounded caution that the central bank needed to see more clear signs of economic strength before lifting rates and threw some blame of her curre