Stocks faded to a weak close Wednesday after Federal Reserve Chairman Ben Bernanke said the drags on the U.S. economy may be worse than previously thought.
Major indexes had been mixed for much of the day but turned lower in mid-afternoon trading as Bernanke spoke at a news conference.
Responding to a reporter's question, Bernanke said that some of the problems plaguing the economy such as weakness in the financial industry and the housing market and "may be stronger and more persistent than we thought."
Earlier, the Fed released a slightly lower forecast for U.S. economic growth this year. The Fed said it now expects the economy to grow between 2.7 percent and 2.9 percent this year, down from its previous estimate of 3.1 percent to 3.3 percent after its last meeting in April.
The Federal Reserve left interest rates unchanged at the end of its two-day meeting Wednesday.
The Dow Jones industrial average and the Standard & Poor's 500 index slumped after Bernanke's cautious remarks about the economy. Bernanke also said Greece's debt crisis was a "very difficult situation."
The Dow closed down 80.34 points, or 0.7 percent, at 12,109.67. The S&P 500 index fell 8.38 points, or 0.7 percent, to close at 1,287.14. The Nasdaq fell 18.07 points, or 0.7 percent, to 2,669.19.
Even with the dimmer outlook, the Fed pledged no new help to boost the economy. The central bank's $600 billion bond-buying program draws to a close at the end of this month.
Among heavily traded companies, FedEx Corp. reported a 33 percent jump in income and said it expects global economic growth to continue. The package delivery company's stock rose 2.6 percent.
Analysts consider results from FedEx and its rival UPS Corp. important indicators for the broader economy because they ship orders for all kinds of businesses.
CarMax Inc. rose 7 percent, the biggest gain in the S&P 500 index. The dealership owner said profit rose 25 percent on higher used-vehicle prices.
Jabil Circuit Inc. rose 3 percent after the electronics part maker said its earnings doubled last quarter.
AeroVironment Inc. jumped 21 percent after the maker of unmanned aerial drones and charging systems for electric cars said its income rose 13 percent.
In Greece, the new government narrowly won a vote of confidence. That may help it push through budget cuts and other austerity measures that it needs to secure more emergency loans.
The cash will help the country at least delay a default on its debt, an event that would hurt banks and the European economy. Worries about a Greek default have weighed on global financial markets since May.
Three stocks fell for every two that rose on the New York Stock Exchange Wednesday. Volume was light at 3.3 billion shares, below the daily average of 3.9 billion over the previous two months.