US stock futures retain sharp losses after claims

U.S. stock-index futures remained steeply under water on Thursday with better-than-expected data on the labor front doing little to curb investor worries about a slowing global economy.

The government reported 264,000 Americans filed for unemployment benefits , less than the 290,000 forecast by economists.

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Weaker retail sales, a decline in producer prices and a surprising drop in the Empire State index were catalysts for broad market volatility on Wednesday. After widespread turbulence, the Dow Jones Industrial Average closed down 173 points, or 1.06 percent, paring losses after an intraday decline of 458 points. The closed 0.8 percent lower.

Although stocks erased much of their losses by the close of trade, investors will be braced for more U.S. economic data—and potentially more turmoil—on Thursday. Influential investor Dennis Gartman told CNBC that the bear market had begun and warned there was going to be "more than a mere 7 to 10 percent correction" in markets.

Read more: Buyers beware, the bear market has begun: Gartman

Thursday's data also includes industrial production at 9:15 a.m. Eastern and the Philadelphia Federal Reserve survey and National Association of Home Builders sentiment survey, at 10 a.m. Treasury capital flow data is due at 9 a.m.

Investors will be watching earnings releases from Google after the market close.

Goldman Sachs reported ahead of the opening bell

Other companies reporting include Blackstone, Delta Airlines, UnitedHealth, Baker Hughes, Snap-on, Mattel, Winnebago, Cypress Semiconductor, Fifth Third, First Republic Bank and PPG ahead of the open. Capital One, SanDisk, Stryker, Advanced Micro and Schlumberger report after the closing bell. An Apple product announcement at 1 p.m. will also be watched by investors.