Kim Hjelmgaard

USA TODAY

Stocks plunged again Friday with Wall Street capping off one of its worst weeks of the year as tumbling oil prices spooked markets. It was Wall Street's first losing week after seven straight weeks of gains.

The Dow Jones industrial average fell 315.51 points, or 1.8%, to 17,280.83. The blue-chip index fell 678 points, or 3.8%, this week, its worst week since Sept. 2011.

The Standard & Poor's 500 index tumbled 33.00 points, or 1.6%, to 2002.33 and closed off the week down 3.5%, its lowest since Oct. 30 and its worst week since May 2012.

The Nasdaq composite index dropped 54.57 points, or 1.2%, to 4653.60 and was down about 2.7% for the week.

"It was a bad week, but similar to other upswings this year, the decline after several highs was moderate and controlled," says Howard Silverblatt, senior index analyst for S&P Indices. "The question, however, remained the same as it was before – is that it?"

Falling oil prices weighed on the stock market again. Oil slumped after the International Energy Agency said global oil demand in 2015 will grow less than previously forecast.

U.S. benchmark oil slipped $2.14, or 3.6%, to $57.81 a barrel. Oil was down 12.6% for the week. Energy stocks in the S&P 500 index fell 2.2%, taking their loss for the year to about 16%.

"The move, especially this week, has been entirely related to oil" said James Liu, global market strategist for J.P. Morgan Funds. "In the fourth quarter you're going to see a lot of pain from the energy sector."

Overseas, European stocks also crated as major benchmarks lost more than 2.5%.

Britain's FTSE dropped 2.5% to 6300.63 and Germany's DAX index tumbled 2.7% to 9594.73. France's CAC 40 fell 2.8% to 4108.93.

In Japan, the Nikkei 225 index rose 0.7% to 17,371.58 but Hong Kong's Hang Seng index dropped 0.3% to 23,249.20. The Shanghai composite index added 0.4% on mainland China.

In economic news, the Labor Department says the producer price index fell 0.2% in November, after rising by the same amount in October. In the past 12 months, producer prices have risen just 1.4%, the smallest yearly increase since February.

Gold fell 0.3%, to $1,222 an ounce. The yield on the benchmark 10-year Treasury note dropped to 2.09% from 2.17% Thursday.

Contributing: Associated Press.

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