U.S. stock futures held sharp gains on Wednesday after data had private-sector job creation increasing in December.
The December ADP unemployment report comes ahead of the nonfarm payrolls on Friday.
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On Wednesday afternoon, minutes from the Federal Reserve's mid-December meeting will be released, and could offer hints as to the timing of interest-rate hikes ahead.
"What would really help is some quantitative guidance on what we would need to see in either the labor market or inflation data to persuade the FOMC's core to alter its plan to begin raising rates in mid-2015. But we suspect that will be lacking from the minutes," said Capital Economics' Paul Ashworth in a research note on Tuesday.