All three indexes ended the week lower for the fourth straight week, as investors sold stocks across all sectors and industries, with technology and consumer staples taking the brunt of the selloff. The tech-heavy Nasdaq composite index fell to its lowest point of the year.

The drop was triggered by lower-than-expected earnings from Microsoft — a rare miss that unnerved investors. And Wall Street saw Amazon.com's lower-than-expected earnings and revenues as a sign consumer spending may be slowing.

Combined with economic data that has pointed to what Federal Reserve chairman Alan Greenspan calls a "soft spot" in the economic recovery, the week was brutal for the markets.

"You take the economic data over the last few weeks, which has been disappointing, and now all these negative earnings outlooks, and then you add in all the worries about energy prices, terrorism, Iraq, the elections — there's a lot to worry about out there," said Michael Sheldon, chief market strategist at Spencer Clarke LLC.

According to preliminary calculations, the Dow Jones industrial average was down 88.11, or 0.9 percent, at 9,962.22. It was the first time the Dow has closed below 10,000 since May 24.

Broader stock indicators were also sharply lower. The Nasdaq composite dropped 39.97, or 2.1 percent, to 1,849.09, its lowest closing in 2004. The Standard & Poor's 500 index was down 10.64, or 1 percent, at 1,086.20.

For the week, the Dow and Nasdaq both fell 1.8 percent, while the S&P 500 was down 1.4 percent. It was the fourth straight down week for the Nasdaq, the fifth for the Dow and the sixth for the S&P 500.

The market has been sinking steadily since early July, when a disappointing jobs report from the Labor Department ended hopes for a summer rally and started giving investors severe doubt about the strength of the economy. Since then, other downbeat economic data and some surprisingly poor second-half earnings outlooks have taken the market lower and lower.

Many analysts expect the major indexes to trade in this lower range for a while.

"We have to get past some of these milestones on the calendar — the conventions, the Olympics, the Fed meeting on Aug. 10, even the elections — and we have to get through them unscathed," said Jeff Kleintop, chief investment strategist for PNC Financial Services Group.

Declining issues outnumbered advancers by about 2 to 1 on the New York Stock Exchange, where volume was very light.