By Sara Sjolin, MarketWatch

Facebook shares drop premarket

U.S. stock futures struggled for direction on Thursday, as investors stayed on the sidelines ahead of second-quarter growth data that could influence the timing of the first Federal Reserve interest-rate hike.

Futures for the Dow Jones Industrial Average slipped 8 points, or 0.1%, to 17,673, while those for the S&P 500 index fell 1.50 points, or 0.1%, to 2,100. Futures for the Nasdaq 100 index rose 4.25 points, or 0.1%, to 4,569.25.

GDP data: The day's key event is likely to be the release of second-quarter gross domestic product data due at 8:30 a.m. Eastern Time. Economists polled by MarketWatch forecast the economy grew by 2.8% in the quarter, staging a rebound after a 0.2% contraction in the first three months of the year.

"Today's 2Q GDP update will weigh heavily on whether the Fed hikes in September or if it will again delay," said John Kicklighter, chief strategist at DailyFX, in a note.

Read:What the huge change to how GDP is calculated means for U.S. economy (http://www.marketwatch.com/story/here-comes-the-big-fix-to-gdp-what-it-says-about-the-us-economy-2015-07-29)

The Fed on Wednesday kept rates on hold as expected, but hinted strongly that it's ready to start tightening monetary policy in the fall (http://www.marketwatch.com/story/fed-will-raise-rates-in-september-2015-07-29), depending on improvement in incoming data.

U.S. stocks closed higher on Wednesday (http://www.marketwatch.com/storyno-meta-for-guid), although action was choppy immediately after the Fed decision and statement. The dollar rose on the expectations of a 2015 rate hike, and the ICE dollar index continued its ascent on Thursday (http://www.marketwatch.com/story/dollar-rises-against-yen-euro-after-fomc-2015-07-30-11033421) as well.

Also on the lineup are weekly jobless claims, due at 8:30 a.m. Eastern. Forecasts are for a climb to 275,000 in the week ended July 25, up from 255,000 in the week before, which was the lowest level since November 1973 (http://www.marketwatch.com/story/us-jobless-claims-plunge-26000-to-255000-lowest-level-since-1973-2015-07-23).

Also at 8:30 a.m., a new advance trade balance report that only focuses on goods is due. It's the first time such a report is released.

Earnings: Reporting ahead of the bell, cable-TV provider Time Warner Cable Inc.(TWC) reported a 19% drop in adjusted second-quarter profit, missing analyst expectations.

Colgate-Palmolive Co.(CL) shares rose 0.8% after the consumer-products company reported earnings that matched forecasts (http://www.marketwatch.com/story/colgate-palmolive-profit-matches-estimates-sales-slightly-short-2015-07-30).

Another consumer-goods company Procter & Gamble Co. (PG) slipped 0.2% after its fourth-quarter revenue slightly missed expectations (http://www.marketwatch.com/story/procter-gamble-beats-profit-expectations-but-provides-downbeat-outlook-2015-07-30).

ConocoPhillips(COP) climbed 2.1% after the oil and gas explorer said it's on track to achieve the higher end of its 2015 production target (http://www.marketwatch.com/story/conocophillips-cuts-capex-plan-as-it-posts-loss-2015-07-30).

Valero Energy Corp.(VLO) is also slated to report premarket.

And after the market closes, earnings from game developer Electronic Arts Inc.(EA), biotech company Amgen Inc.(AMGN) and online networking site LinkedIn Corp.(LNKD) are on tap.

Movers & shakers: Shares of Facebook Inc.(FB) lost 1.4% ahead of the bell after the social-media company late Wednesday reported a drop in second-quarter earnings (http://www.marketwatch.com/story/facebook-beats-profit-views-while-expenses-jump-2015-07-29-16485210).

Whole Foods Market Inc.(WFM) plunged 14% ahead of the open after the supermarket chain on Wednesday posted earnings that slightly missed forecasts.

U.S.-listed shares of Nokia Corp.(NOK) jumped 5.9% in premarket trading after the Finnish telecom-equipment company reported better-than-expected second-quarter profit (http://www.marketwatch.com/story/nokia-beats-expectations-on-higher-software-sales-2015-07-30-14854044).

U.S.-listed shares of Anheuser Busch InBev NV (ABI.BT) slumped 5% ahead of the bell after the brewer said profit fell in the second quarter (http://www.marketwatch.com/story/ab-inbev-profit-falls-on-us-europe-weakness-2015-07-30), as weakness in the U.S. and Europe weighed on sales volume.

Shares of Synergy Pharmaceuticals Inc.(SGYP) soared 25% after the drug maker said test results were positive for its plecanatide treatment for patients with chronic idiopathic constipation.

Other markets: Stock markets in Asia closed mixed (http://www.marketwatch.com/storyno-meta-for-guid), with the Shanghai Composite Index shaving off an earlier gain and ending 2.2% lower.

European stocks were mixed, with the Stoxx Europe 600 index inching higher on the back of a round of well-received earnings reports (http://www.marketwatch.com/storyno-meta-for-guid).

Gold (http://www.marketwatch.com/storyno-meta-for-guid) declined to trade around a 5 1/2 -year low, while crude-oil futures rose 0.7%.

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