US Markets

Futures struggle for gains amid Yellen, data

U.S. stock futures traded mixed on Wednesday as investors digested data and prepared remarks by U.S. Federal Reserve Chair Janet Yellen for a speech to Congress later in the day.

In the remarks, the Fed chair said the central bank remains on track to raise rates this year if the economy evolves as expected. She said unemployment should decline but inflation remains below the Fed's target. Greece and China topped the list of uncertainties in Yellen's testimony.

U.S. June producer price data showed an increase of 0.4 percent in June, while the July Empire State Survey came in at 3.9, topping June's negative 2 read.

June industrial production data rose 0.3 percent, with capacity utilization at 78.4 percent, up a touch from May.

Treasury yields rose, with the 2-year yield rising to 0.67 percent and the 10-year briefly near 2.43 percent, up from 2.39 percent earlier.

The dollar strengthened, with the euro falling below $1.10.

Fed chief Yellen appears before the House Financial Services Committee at 10 a.m. ET to deliver her testimony on the economy.

Second-quarter earnings season, a key vote in Greece's parliament to pass legislation needed to secure a third bailout and renewed turbulence in China's stock market were also in focus.

Federal Reserve Bank Chair Janet Yellen speaks following a meeting of the Federal Open Market Committee June 17, 2015 in Washington, DC.
Getty Images

The Dow futures fluctuated around the flatline after earlier trading about 10 points higher. Stocks posted their fourth consecutive day of gains Tuesday.

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Data on Tuesday showed June retail sales fell 0.3 percent, compared with analyst expectations for a rise.

The Fed's Beige Book survey is due at 2:00 p.m.

Weekly mortgage applications fell 1.9 percent on a seasonally adjusted basis, according to the Mortgage Bankers Association (MBA).

Overseas, China data showed the national GDP rose 7 percent in the second quarter from a year earlier. Analysts polled by Reuters had anticipated a 6.9 percent rise.

The data failed to lift sentiment in China's stock market, with the benchmark Shanghai Composite tumbling more than 4 percent before closing 3 percent lower.

Read More 'Hard won' China Q2 growth prompts new data questions

Sharp falls in Chinese stocks in the past month have fanned concerns about a protracted slowdown in the Chinese economy, undermining sentiment across global markets.

And Greece, another risk factor for investors, also remains in the spotlight with lawmakers due to vote on sweeping austerity and reform measures by midnight Wednesday to secure further funds from international creditors.

Greek Prime Minisiter Alexis Tsipras faces some opposition from within his anti-austerity Syriza party to the legislation.

"Notable elements of the ruling coalition have made clear that they will not vote in favour. But the legislation seems highly likely to be adopted, not least thanks to the support of the opposition New Democracy, To Potami and Socialist (PASOK) parties," analysts at Daiwa Capital Markets said in a note.

"Such a result will raise existential issues about the coalition, with a minority government led by Tsipras, rather than a pro-euro Government of National Unity, perhaps most likely eventually to result over the near term," they added.

And as second-quarter earnings season gets underway, Wall Street will digest a slew of reports. Bank of America, BlackRock, US Bancorp, Delta Air Lines and PNC Financial, Intel and Netflix all report earnings this session.

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Elsewhere, European shares turned higher, while oil prices were a touch weaker a day after an Iran nuclear deal was finally reached.