US stocks see-sawed in more noncommittal trade Wednesday to close almost flat for the third straight session, with fresh data sending more mixed signals on the economy. After adding 0.3 percent in the early afternoon, the Dow Jones Industrial Average finished up just 4.49 points (0.03 percent) at 13,107.48. The broad-based S&P 500 added 1.19 (0.08 percent) at 1,410.49, while the tech-rich Nasdaq rose 4.05 (0.13 percent) to 3,081.19. Economic data continued to come in mixed: second-quarter growth was revised upward to 1.7 percent from 1.5 percent, and data on pending home sales in July was strong. But the Federal Reserve\'s periodic Beige Book survey of regional economies, a key input into policy decisions, was slightly less buoyant than the previous report, suggesting the central bank sees growth as having slowed slightly since July.