Sentiment could be further dampened the coming week with the government expected to significantly revise lower the economic growth chalked up in the second quarter period.
Shares were especially pulled down by government data Thursday showing new weekly jobless benefit claims jumping to the highest level in nine months, and slower regional manufacturing activity.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
For the week, the Dow Jones Industrial Average lost 0.87 percent to 10,213.62 and the broader S&P 500 index dropped 0.7 percent to 1.071.69 as both indexes extended a second consecutive week of losses.
The technology-rich Nasdaq composite index rose 0.29 percent to 2,179.76.
"The market is virtually flat for the week... There is so much uncertainty and indecision right now," said Ryan Detrick, senior technical strategist at Schaeffer's Investment Research.
"We've seen continued deterioration of economic data, the jobless claims highest in nine months specifically. Recent data continues to confirm the economy, without question, is slowing."
The government on Friday is expected to revise sharply lower the second quarter gross domestic product growth to 1.4 percent from the previously projected 2.4 percent, most analysts said.
Home sales are also expected to show a sharp fall in July.
"Indicators next week are expected to produce somewhat ambiguous readings, but confirm in general a fairly sharp slowdown in growth momentum in the past three or four months," IHS Global Insight analysts said in a note.
"Second quarter real GDP growth is expected to undergo a significant downward revision," they said.
But on the corporate level, the past week saw a flare of upbeat action with a string of positive earning reports from market heavyweights, indicating a rise in consumer spending, the engine of the US economy.
The world's largest retailer Wal-Mart, home improvement chain Home Depot, discount retailer chain Target as well as John Deere, the world's largest tractor manufacturer, all presented strong quarterly earning.
And on Thursday, computer manufacturers Hewlett-Packard and Dell posted a rise in earnings.
The market was further animated by General Motors' landmark move to sell its stocks to the public as America's largest auto manufacturer seeks to free itself of government ownership following bankruptcy in 2009.
The markets also rose following news that the Anglo-Australian BHP Billiton, the world's largest mining firm, would take a direct buying bid to shareholders of the Canadian group Potash, the world's top fertilizer producer after the latter rejected an initial acquisition offer.
Chip manufacturer Intel added to the corporate activity by announcing the acquisition of Internet security firm McAfee for nearly seven billion dollars.
But the developments failed to excite the traders.
"Companies have a lot of cash, but the cash is going in circles and is not used for productive investments but for industrial strategies. This is not enough to support the stock markets which are showing uncertainty on the US recovery," analyst Evariste Lefeuvre of Natixis investment house said.
