Aug. 20, 2011 (Bloomberg) -- U.S. stocks tumbled, sending the Standard & Poor’s 500 Index to its biggest four-week loss since March 2009, as concern the global economy is stalling overshadowed the cheapest valuations in 2 1/2 years.
Hewlett-Packard Co. (HPQ) plunged 27 percent this week, the most since the October 1987 market crash, after a strategy shift undermined confidence in its managers. Technology, industrial and raw-material companies in the S&P 500 dropped at least 6.9 percent, the most among 10 groups. Caterpillar Inc. (CAT) and Alcoa Inc. (AA) retreated more than 8.4 percent after some of the world’s biggest banks -- Morgan Stanley, JPMorgan Chase & Co. and Citigroup Inc. -- slashed economic growth forecasts.
The S&P 500 lost 4.7 percent to 1,123.53. It has sunk 16 percent since July 22 as about $3 trillion was erased from the value of U.S. equities, according to data compiled by Bloomberg. The Dow Jones Industrial Average fell 451.37 points, or 4 percent, to 10,817.65 this week, extending its four-week decline to 1,863.51 points.
“We’re in a little bit of a tug of war,” David Joy, the Boston-based chief market strategist at Ameriprise Financial Inc., said in a telephone interview. His firm oversees $693 billion. “On the one hand, there’s the real concern about what’s going on in Europe, about the pressure on the banking system and weakness in the global economy. On the other, an opposing force seems to be an interest in buying at attractive equity valuations.”
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