NEW YORK (AP) -- Stocks climbed Thursday afternoon after spending the morning barely in the green. The Standard & Poor's 500 index crossed 1,400 for the first time since June 2008, and the Dow Jones industrial average was on track to close higher for a seventh straight day.
Positive economic data on unemployment and wholesale prices helped drive the market early, and stocks moved even higher after a sharp, sudden drop in the price of oil.
Oil dropped almost $2 per barrel in minutes after a report that the United States and Britain had agreed to release oil from emergency reserves. The White House later said those reports were inaccurate, and oil prices recovered.
The Dow was at break-even when the oil report came out, and the average started a steady climb. Just before 2 p.m. EDT, it was up 34 points at 13,227. A seventh consecutive gain would be the longest streak since February 2011.
The Standard & Poor's 500 index was up six points at 1,400 and traded as high as 1,402 earlier in the day. It had not crossed 1,400 during a trading day since June 6, 2008, and has not closed higher than 1,400 since June 5, 2008.
The Nasdaq composite index added 10 points to 3,051.
Investors applauded further signs of an improving economy.
The government said applications for unemployment benefits fell last week to 351,000, matching a four-year low. When applications stay below 375,000, it usually signals that hiring strong enough to lower the unemployment rate.
"We've been sputtering for the last couple of days, but now we're seeing those strong jobs numbers really drive the market higher," said Joe Bell, senior equity strategist at Schaeffer's Investment Research. "We've seen strong reports for the last eight to 10 weeks, and this is just adding to signs of economic strength."
A separate report showed that prices paid by wholesalers rose less than expected in February, despite a spike in gasoline prices. The producer price index has increased 3.3 percent in the past year, the smallest gain since August 2010.
In Asia, markets mostly fell after Chinese Premier Wen Jiabao said curbs that have slowed a run-up in housing prices will remain in place, despite fears that the effort could contribute to the nation's economic slowdown.
The benchmark Shanghai Composite Index lost 0.7 percent. But Hong Kong's Hang Seng closed 0.2 percent higher, and Japan's Nikkei index rose 0.7 percent as the yen continued to decline from record highs against the U.S. dollar.
Markets in Europe were mostly higher. Britain's FTSE 100 index fell 0.2 percent, but France's CAC 40 index gained 0.1 percent, Germany's DAX index gained 0.6 percent.
Among the stocks making big moves on Thursday:
-- CSX Corp. jumped 6 percent, most than any stock in the Dow, after its chief financial officer said at a conference that the railroad expects the improving economy to drive record first-quarter earnings.
-- Cisco Systems Inc. slipped 1 percent after it announced a $5 billion deal to buy NDS Group Ltd. from News Corp. Shares of the owner of Fox News and The Wall Street Journal edged higher.
-- Sears Holdings Corp. shares gained 1 percent after the troubled department store chain said its top investor tried to ease vendors' concerns early this year by taking on some of the risk that they would face if Sears filed for bankruptcy.
-- AMC Networks, a spinoff of Cablevision that owns the cable networks AMC, IFC and Sundance Channel, dropped 3 percent after its fourth-quarter earnings fell short of Wall Street estimates.
AP Business Writer Daniel Wagner in Washington contributed to this report.