Stocks closed lower on Wall Street Wednesday. Analysts say investors, already cautious, were scared off by more signs that U.S. businesses are hurting in a weaker U.S. economy. The Dow Jones Industrial Average dropped 76 points, about three quarters of 1%, to 10,871. The broader Standard & Poor's 500 index lost 14 points, 1%, while the tech-weighted NASDAQ composite closed more than 2% lower.