U.S. stocks fell on Friday, extending a rout that had the S&P 500 erasing its biggest rally in a year, with computer-chip manufacturers especially hard hit a day after Microchip Technology lowered its sales outlook. "Exhaustion has almost set into the market. The volume is getting lower because people don't know what to do," said JJ Kinahan, chief strategist at TD Ameritrade. "With the Fed going away, and the slowdown in Europe, the market is trying to figure out are these valuations fair, that's what this whole week has been about," said Kinahan. Equities fell to session lows after Standard & Poor's downgraded the ... (full story)