U.S. Stocks Fall as Oil Prices Slump; Federal Reserve in Focus This Week

U.S. stocks moved lower Monday as oil prices dipped back below $50 a barrel. The declines came amid fears of more supply from producers in Iraq, Nigeria and Iran. Oil prices are up 20 percent since the beginning of August, before Monday's pullback. Meanwhile, the markets await Federal Reserve Chair Janet Yellen's speech on Friday, as Fed officials gather in Jackson Hole, Wyoming for an economic conference. Analysts don't expect any major changes in Yellen's tone about the economy and interest rate hikes. 'I expect [Yellen] to be pretty balanced and go with the same message she's been going with which has been that its data point dependent rather than anything else,' said Ian Winer, head of equity trading at Wedbush Securities, based in Los Angeles. Valeant Pharmaceuticals (VRX) is getting a new chief financial officer: Paul Herendeen, a former executive at Zoetis. This comes after the troubled drugmaker replaced its CEO back in April, with Joseph Papa taking control of the company. TheStreet's Scott Gamm reports from Wall Street.