U.S. stock index futures indicated a lower open on Tuesday, as second-quarter earnings season gets underway.
Aluminium producer Alcoa is due to report second-quarter results after the close, and although the company was dropped from the Dow Jones Industrial Average last year, the figures will be closely watched. Analysts are looking for earnings per share of 12 cents on revenue of $5.65 billion. In the second quarter 2013, the company reported revenue of $5.85 billion.
On the economic data front, the JOLTS job openings report is due at 10 a.m. ET on Tuesday.
"On the JOLTs report, it's been well publicized that this is a key labor market data point for the Fed so the trends in hiring, layoffs and quit rates will be closely watched," Deutsche Bank strategist Jim Reid said in a morning note.
Both the Richmond Fed's Jeffrey Lacker and Minneapolis Fed's Narayana Kocherlakota are also due to speak later in the day.
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Their comments will be closely watched ahead of the minutes from the U.S. Federal Reserve's June meeting on Wednesday. The publication will take on all the more significance after last week's non-farm payrolls data came in much stronger than expected.
"We expect some insights into the change in the committee's forecasts and an indication that it is putting less emphasis on the recent weakness in GDP growth and more on the labor market," Barclays analysts said in a morning note.
Meanwhile in Europe and Asia, stocks traded mostly lower on Tuesday, tracking the slip in U.S. equities on Monday, when stocks retreated from all-time highs.