Here comes ISM services PMI ...

Markit Economics and the Institute of Supply Management will release their monthly reports on the services sector shortly.

Economists forecast Markit's purchasing manager's index at 53.1. ISM's index is expected at 57.

The services sector is where most US economic activity happens.

"Like its manufacturing cousin, the ISM non-manufacturing index stands firmly in expansionary territory, at a level of 57.6 as of February (the highest level since October 2015)," said Wells Fargo's Sam Bullard in a preview. "While regional services sector activity looks to have picked up from February (both the Dallas Fed and Richmond Fed surveys), our model signals a pullback in the headline national index to a still-robust level of 57.1."

More to come ...