US stocks extended losses on Wednesday as concerns over global economic slowdown and sluggish corporate earnings continued to weigh on the market. When the market closed, the Dow Jones Industrial Average tumbled 128.56 points, or 0.95 percent, to 13,344.97. The Standard& Poor's 500 Index fell 8.92 points, or 0.62 percent, to 1,432.56. The Nasdaq Composite Index dropped 13.24 points, or 0.43 percent, to 3,051.78. Alcoa and Chevron led the blue-chip Dow down for the third straight day after the two heavyweights released downbeat reports. Alcoa plummeted 4.60 percent after the aluminum producer reported better-than-expected earnings but lowered its 2012 outlook for aluminum demand due to China slowdown. Chevron also plunged more than 4 percent on Wednesday after the country's second-largest oil company warned late Tuesday that slumping oil prices and production would cause earnings to be " substantially lower". Market sentiment was still hammered by the report from the International Monetary Fund (IMF) in the previous session. The IMF downgraded the growth forecasts for the global economy to 3.3 percent for 2012 and 3.6 percent for 2013 from the July projections of 3.5 percent and 3.9 percent respectively. The IMF said the world economic recovery has suffered new setbacks, and uncertainty weighed heavily on the outlook. It called for U.S. and European policymakers to accelerate efforts to tackle challenges. Concerns over European debt crisis remained. The International Monetary Fund said banks in Europe may need to sell off 4.5 trillion dollars of assets through 2013 if policy markers fail to implement fiscal tightening measures. Investors were also fretted about the situation in Spain, expecting the debt-ridden country to ask for a bailout for its public finances even after euro zone finance ministers delivered a united defense of Spain at a meeting this week, saying the country did not need a bailout at the moment. In the afternoon trading, the Federal Reserve released its Beige Book business survey, which is based on accounts from the 12 district Fed banks, saying the U.S. economy was expanding " modestly" in late August and September, supported by improvements in housing and auto sales, even as the labor market showed little change. However, the survey did little to boost the market. In other markets, the U.S. dollar retreated in late session and traded lower against most of its major counterparts after the ICE dollar indexes broke 80 for the first time in a month. US crude price also fell on Wednesday as concerns about global economic growth offset escalating tensions in the Middle East. Light, sweet crude for November delivery dropped 1.14 dollars, or 1.23 percent, to settle at 91.25 dollars a barrel on the New York Mercantile Exchange.