U.S. stock index futures furthered already steep declines after data had orders for U.S. durable goods unexpectedly falling in December, adding to a bearish view as corporate earnings disappointed.
Orders for business equipment fell 3.4 percent last month, illustrating the slowing global economy is impacting U.S. multinationals.
Separately, home prices in 20 cities rose 4.3 percent in November, according to the S&P/Case-Shiller index of property values.
Earnings season is poised to gather steam this week, with some of Wall Street's biggest names lined up to report. Apple releases its earnings after the close on Tuesday, with analysts expecting the tech firm to beat consensus.