MARKET SNAPSHOT: U.S. Stocks End Mostly Lower After Bernanke Speech

By Anora Mahmudova, MarketWatch

NEW YORK (MarketWatch) -- U.S. stocks ended a choppy trading session mostly lower on Friday after Federal Reserve Chairman Ben Bernanke defended the extraordinary measures undertaken by the central bank to boost the economic recovery.

The S&P 500 (SPX) slipped less than a point to end at 1,831.37, leaving it down 0.5% for the week.

The Dow Jones Industrial Average (DJI) closed up 28.64 points, or 0.2%, at 16,469.99, but finished the week marginally lower.

The tech-heavy Nasdaq Composite (RIXF) shed 11.16 points, or 0.3%, to 4,131.91 on Friday and lost 0.6% for the week.

Volumes on Wall Street were thin, with many traders still on vacation. Also, a major storm in the Northeast hampered travel and states of emergency were declared in New York and New Jersey.

"Next week volumes will rise as market participants will be back to work and investors will be reallocating portfolios for 2014," said Channing Smith, managing director at Capital Advisors.

U.S. stocks perked up briefly in the afternoon after the Fed Chairman Bernanke spoke at the American Economics Association conference. He defended Fed policy, including its asset-buying program.

Last month, the Fed said it would reduce its monthly asset purchases by $10 billion to $75 billion, but stressed it was committed to low interest rates until further declines in the unemployment rate. Critics of the bond-buying program see the Fed's $4 trillion balance sheet as a potential future cause of inflation, while proponents worry the withdrawal of monetary stimulus will hamper the economic recovery.

During the session, markets reacted negatively to comments by Philadelphia Fed President Charles Plosser, who said the central bank may have to be "aggressive" in raising interest rates. Plosser is known for his hawkish views and becomes a voting Federal Open Market Committee member this year.

Investors digested data on December car sales, which are often seen as a barometer of consumer confidence. Ford Motor Co. (F), the second-largest auto maker, reported a 2% gain in net sales in December to 218,058 vehicles. Analysts expected a 5.9% gain. Ford shares closed 0.5% higher, after earlier weakness.

Privately owned Chrysler Group LLC reported a 5.7% increase in sales last month to 161,007 units, missing analysts' expectations.

General Motors Co. (GM.XX) shares dropped 3.4% after the car maker reported a decline in U.S. vehicle sales for December to 230,157 units, down 6.3% from a year ago, while analysts expected a rise of 0.8%.

FireEye Inc. (FEYE) shares surged nearly 39%. The computer-security firm on Thursday said it acquired Mandiant Corp., a company known for its report linking cyberattacks on U.S. companies to the Chinese military that was published in early 2013, in a deal worth about $1 billion.

Delta Air Lines Inc. (DAL) climbed 5.5% after the firm said its passenger unit revenue was up 10% in December.

Rite Aid Corp. (RAD) advanced 8.5% after the drugstore chain said same-store sales increased 2.9% in December over the same period a year ago, due to growth in its pharmacy division.

Shares of Twitter Inc. (TWTR) rose 2.2%.

Sprint Corp. (S) shares fell 4.4%. They declined 3.3% on Thursday after a downgrade from Cowen & Co. to a market perform rating from outperform, even as the firm raised its price target on Sprint to $8.25 from $7.50.

Owens Illinois Inc. (OI) fell 1.9%. Analysts at Bank of America Merrill Lynch reportedly downgraded the glass company to neutral from buy, according to the Analyst Ratings Network.

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