The August US Services Purchasing Managers' Index conducted by Markit came in at 55.1 percent, down 4.8 from the final July estimate of 59.9.

Here is the opening from the latest press release:

Commenting on the latest survey results, Chris Williamson, Chief Business Economist at IHS Markit, said:

“Growth slowed sharply in the US service sector in August, joining the manufacturing sector in reporting a marked cooling in demand and encountering growing problems finding staff and supplies. Jobs growth almost stalled among the surveyed companies in August and supplier lead times are lengthening at a near record rate.

“While the resulting overall pace of economic growth signalled is the weakest seen so far this year, backlogs of uncompleted work are rising at a rate unprecedented in at least 12 years, underscoring how supply and labor shortages are putting the brakes on the recovery. The inevitable upshot is higher prices, with firms' input costs and selling prices rising at increased rates again in August, continuing the steepest period of price growth yet recorded by the survey by a wide margin.

“Encouragement comes from a rise in business expectations about the year ahead, though optimism in the service sector in particular remains off the high seen in the second quarter, to a large extent reflecting concerns over the spread of the Delta variant.” [Press Release]

Here is a snapshot of the series since mid-2012.

Here is an overlay with the equivalent PMI survey conducted by the Institute for Supply Management, which they refer to as "Non-Manufacturing" (see our full article on this series here). Over its history, the ISM metric has been significantly the more volatile of the two.

The next chart uses a three-month moving average of the two rather volatile series to facilitate our understanding of the current trend. Since early in 2016, the ISM metric has shown stronger growth than the Markit counterpart.