- Slideshow: Stock Markets
And in Germany, Daimler's stock fell sharply after the automaker reported lower third-quarter earnings and abandoned its 2008 profit and revenue forecast. That followed news in the U.S. late Thursday from Microsoft Corp., which issued a weaker-than-expected forecast for its fiscal second quarter, pointing to the economy.
"People have been saying that we're in a recession. This is the realization," said Scott Fullman, director of derivatives investment strategy for WJB Capital Group in New York.
It is clear that many investors are convinced the world economy is headed for a severe downturn even as governments have raced to jump-start credit markets on the hope that a return of more normal lending levels by banks and other financial houses will fan economic activity.
But some say the recent pullbacks have been set off by forced selling, keeping some bargain-seeking traders from entering the market.
"There's nothing new going on," said Scott Bleier, president of market advisory service CreateCapital.com. "This is all about the unwinding of massive leverage."
Bleier attributed the declines to margin calls and investors in hedge funds and mutual funds cashing out. A margin call occurs when investors are forced to sell holdings, like stock, to raise cash at the demands of brokers.
"Market participants' fear is not that the economy is slowing," he said. "The fear is there is an endless supply of things for sale, regardless of price."
Steve Gross, principal at alternative investment and advisory firm Penso Capital Markets, said most large hedge funds have already slashed their positions. Instead, he sees a lack of demand: "There are no buyers at all."
Investors were nervous going into the session after U.S. stock futures — the bets traders place on where the market will go — fell so sharply before Friday's opening bell that selling halts were imposed.
By the close, according to preliminary calculations, the Dow fell 312.30, or 3.59 percent, to 8,378.95 after falling 504 in the early going. Still, the blue chips remained above the 8,000 level; at its recent low of Oct. 10, the Dow traded as low as 7,882.51.
Broader stock indicators also fell. The S&P 500 index declined 31.34, or 3.45 percent, to 876.77, and the Nasdaq composite index fell 51.88, or 3.23 percent, to 1,552.03.
Friday's finish was the lowest for the Dow since April 25, 2003, when it ended at 8,306.35. For the S&P, it was the lowest ending since April 11, 2003 when the index finished at 868.30.
The Russell 2000 index of smaller companies fell 18.80, or 3.84 percent, to 471.12.
Declining issues outpaced advancers by about 5 to 1 on the New York Stock Exchange, where volume came to 1.58 billion shares.
Friday was the 79th anniversary of the day that, according to many market historians, the October 1929 stock market crash began. Selling began on Thursday, Oct. 24, and accelerated the following week on the days that have since become known as Black Monday and Black Tuesday, Oct 28 and 29.
For the week, the Dow fell 5.35 percent, the S&P 500 lost 6.78 percent and the Nasdaq fell 9.31 percent.