Stocks: Fear keeps investors sidelined

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NEW YORK (CNNMoney) -- U.S. stocks were set to open lower Thursday, as concerns about Greece's debt overshadowed stronger-than-expected reports on the housing market and unemployment.

Dow Jones industrial average (INDU), S&P 500 (SPX) and Nasdaq (COMP) futures were down ahead of the opening bell. Futures measure current index values against perceived future performance.

U.S. stocks finished sharply lower Wednesday, after gloomy manufacturing data and news that eurozone officials failed to agree on a rescue plan for Greece.

The market has been weakening since the start of May, and stocks are on track to decline for the 7th straight week.

Economy: Investors had plenty of economic data to mull over before the bell -- with initial unemployment claims from the Labor Department, and May housing starts and building permits data from the Commerce Department. All reports came in stronger than expected.

The government reported that jobless claims slipped to 414,000 last week, down 16,000 from the prior week. Economists had expected a more modest decline in weekly claims of 421,000.

Housing starts jumped 3.5% in May -- more than expected -- to a seasonally adjusted annual rate of 560,000. They were forecast to have risen to a 540,000 annual rate in May, from 523,000 in April.

Building permits also defeated expectations, rising 8.7% to a seasonally adjusted annual rate of 612,000 in May, from the prior month's rate of 563,000. Economists had expected permits to edge lower to a 548,000 annual rate.

The Federal Reserve Bank of Philadelphia will release its June manufacturing survey at 10 a.m. ET.

The pain of Greece's crisis

World markets: Deepening worries about Greece's debt are likely to keep investors on their toes until a bailout for the country is agreed upon by eurozone officials. As protesters continued to rally against austerity measures Thursday, Greek Prime Minister George Papandreou reportedly said he will introduce a new government and take a vote of confidence in Parliament.

European stocks tumbled about 1% in morning trading. Britain's FTSE 100 slumped 1.3%, the DAX in Germany fell 1% and France's CAC 40 dropped 1.1%.

Asian markets ended sharply lower. The Shanghai Composite slid 1.5%, the Hang Seng in Hong Kong dipped 1.8% and Japan's Nikkei lost 1.7%.

Companies: Natural-gas pipeline company Energy Transfer Equity L.P. (ETE, Fortune 500) will buy Southern Union Co. (SUG) for $7.9 billion. The news sent shares of Southern Union nearly 17% higher in premarket trading.

Shares of Finisar (FNSR) slumped nearly 18% early Thursday, after the fiber-optic equipment maker released results late Wednesday, forecasting first-quarter earnings to be significantly lower than estimated.

Supermarket chain owner Kroger (KR, Fortune 500) will report quarterly results before the opening bell, with analysts expecting earnings of 64 cents per share.

BlackBerry maker Research in Motion (RIMM) will report earnings after the closing bell, which are forecast to come in at $1.32 a share.

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Currencies and commodities: The dollar strengthened against the euro and the British pound, but slumped versus the Japanese yen.

Oil for July delivery slipped 39 cents to $94.42 a barrel, after dropping more than 4% on Wednesday and hitting the lowest level since February.

Gold futures for August delivery rose $1.20 to $1,527.40 an ounce.

Bonds: The price on the benchmark 10-year U.S. Treasury rose, pushing the yield down to 2.94% from 2.97% late Wednesday.