Markit Economics released final services purchasing managers' index (PMI) for the U.S. on Friday. Final U.S. services purchasing managers' index (PMI) fell to 51.3 in May from 52.8 in April, up from the preliminary reading of 51.2.

A reading above 50 indicates expansion in the sector, a reading below 50 indicates contraction of activity.

The decline was driven by a slower growth in output, new orders and emplyoment.

"The service sector reported one of the weakest expansions seen since the recession in May, adding to signs that any rebound of the economy in the second quarter may be disappointingly muted," Chief Economist at Markit Chris Williamson said.

"Add these disappointing service sector numbers to the downturn now being seen in manufacturing, and the PMI surveys point to GDP growing at an annualised rate of just 0.7-8% in the second quarter, notwithstanding any marked change in June," he added.