By Fred Imbert, CNBC–

  • At around 03:15 a.m. ET, Dow futures slipped 27 points, indicating a negative open of more than 35 points.
  • Futures on the S&P and Nasdaq were both seen marginally lower.
  • Official U.S. GDP data is expected to be published at around 8:30 a.m. ET, with consumer sentiment figures for April set to follow slightly later in the session.

U.S. stock index futures were slightly lower Friday morning, as market participants prepared for another deluge of corporate earnings and awaited key economic data.

At around 03:15 a.m. ET, Dow futures slipped 27 points, indicating a negative open of more than 35 points. Futures on the S&P and Nasdaq were both seen marginally lower.

Market focus is largely attuned to economic developments, amid speculation that figures later in the session could show the U.S. economy outperforming the rest of the developed world.

A string of robust numbers for the world’s largest economy has prompted analysts to revise up their forecasts for expansion and the latest Reuters poll is for annualized growth of 2%.

Meanwhile, the closely-watched projection of gross domestic product (GDP) from the Atlanta Federal Reserve is expecting an outcome of 2.7%, a massive turnaround from a few weeks ago when it stood at 0.5%.

Official U.S. GDP data is expected to be published at around 8:30 a.m. ET, with consumer sentiment figures for April set to follow slightly later in the session.

In corporate news, Chevron, Exxon Mobil and American Airlines are among some of the major companies scheduled to report their latest quarterly figures before the opening bell.

On Thursday, the Dow fell 134.97 points to 26,462.08 as shares of 3M dropped 12.9% after the company reported earnings that were much lower than analysts had expected.

The S&P and Nasdaq fared better than the Dow, as Facebook and Microsoft jumped on strong quarterly numbers.