U.S. stock index futures point to a lower open on Wednesday ahead of the publication of a variety of economic data including the Labor Department's Producer Price Index (PPI), the Core Producer Price Index, Industrial Production and Capacity Utilization report, and the New York Empire State Manufacturing Index among others.

Futures on the Dow Jones Industrial Average were down 0.03 percent, futures on the Standard & Poor's 500 Index dropped 0.17 percent and those on the Nasdaq 100 Index lost 0.03 percent.

Investors are likely to focus on the Department of Labor's Producer Price Index (PPI) - the leading indicator of consumer price inflation - for April to be published on Wednesday at 8:30 a.m. EDT. The PPI, which measures the change in the price of goods sold by manufacturers, is estimated to remain little changed in April from the 0.6 percent decline registered in the previous month.

The Core Producer Price Index (PPI) for April also released by the Department of Labor on Wednesday, which measures the change in the selling price of goods and services sold by producers, excluding food and energy, is likely to remain flat at 1.7 percent.

Investors will also focus on the Industrial Production and Capacity Utilization report to be published before the opening bell. Industrial production that measures the change in the total inflation-adjusted value of output produced by manufacturers, mines and utilities is expected to show a decline of 0.2 percent in April against the 0.4 percent recorded in March. The capacity utilization rate, the percentage of production capacity being utilized in the United States, may drop to 78.3 percent from 78.5 percent registered in the previous month.

Investors also await the New York Empire State Manufacturing Survey for May that rates the relative level of general business conditions in New York State, which is expected to be released at 8:30 a.m. ET. The Empire State manufacturing survey index released by the Federal Reserve Bank of New York is expected to post an increase of 4.0 for May, higher than a reading of 3.0 in April. The reading is compiled from a survey of about 200 manufacturers in New York State. A reading above zero indicates improving conditions.

In addition, investors are also expected to keep a close watch on the Treasury International Capital (TIC) Net Long-Term Transactions, which measures the difference in value between foreign long-term securities purchased by the U.S. citizens and U.S. long-term securities purchased by foreign investors. Economists predict the TIC data scheduled to be released on Wednesday to record a steep gain of $43.4 billion against a $17.8 billion deficit recorded in the previous term.

Rising optimism among investors pushed the U.S. markets to new record highs on Tuesday. The Dow Jones Industrial Average rose 0.82 percent or 123.57 points to close at 15215.25, the S&P 500 Index gained 1.01 percent or 16.57 points to close at record high of 1650.34, while the Nasdaq Composite Index gained 0.69 percent or 23.82 points to end the session at 3462.61.

Earlier, the Small Business Optimism Index, released by the National Federation of Independent Business (NFIB) on Tuesday, beat expectations and rose to a six-month high of 92.1. The index, which measures the health of small businesses in the U.S., was expected to nudge up to 89.8 in April, from 89.5 in March.

"We keep getting bits of slightly better news that tells you the economy is OK," said Paul Zemsky, market strategist at ING Investment Management. "It's not going gangbusters, but it's not falling off a cliff," he added, according to a CNNMoney report.

European markets opened lower on Wednesday after growth data from the top two euro zone economies deflated sentiments in early trade. France entered recession after economic activity shrunk 0.2 percent, a third contraction in the last four quarters, while Germany's growth rate for the first quarter was lower-than-expected at 0.1 percent.

London's FTSE 100 declined 0.2 percent in early deals. France's CAC-40 was down 0.4 percent. Germany's DAX-30 Index slid 0.1 percent.

Most of the Asian markets traded high on Wednesday, when Japanese stocks shot up to a new five-and-a-half-year-high as export companies' stocks rallied on continued yen weakness.

Earlier, the Nikkei closed up 2.29 percent at 15,096.03. South Korea's KOSPI gained 0.12 percent to rise to 1,971.26 towards close.

Hong Kong's Hang Seng rose 0.50 percent to 23,044.24 by market close. In China, the Shanghai Composite index rose 0.35 percent to 2,224.80.