Earnings could be a particular challenge for stocks this quarter, with analysts expecting a 4.8 percent decline in S&P 500 profits, according to Thomson Reuters. So far, there's been a trickle of reports, but the season gains momentum Wednesday with results from the major financials and others, like Delta Airlines, Kinder Morgan and Netflix reporting after the close.
JPMorgan, which is seen as a bellwether for the rest of the financial sector, earned $1.32 per share, excluding $2.2 billion in tax benefits and other items. Volatile financial markets hit revenues, which fell 6.4 percent to $23.5 billion.
On the data front U.S. retail sales barely rose in September as cheaper gasoline weighed on service station receipts, while producer prices posted their biggest decline in 8 months.
August business inventories data are also due at 10:00 a.m. and the U.S. Federal Reserve's latest Beige Book at 2:00 p.m.
Chinese inflation data, released overnight also weighed on sentiment, cooling more than expected last month, adding to concerns about the health of the world's second-biggest economy.
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China's consumer price index (CPI) rose 1.6 percent in September from a year earlier, against forecasts of a 1.8 percent rise from a Reuters poll and following August's 2 percent gain.
The weak data weighed on Asian and European stocks, with major indices in Europe falling in the region of 1 percent in mid-morning London trade.
China's share markets slid into negative territory in the afternoon trading session, with the Shanghai Composite ending down 1 percent.
CNBC's Patti Domm and Reuters contributed to this story.