Economic activity in the U.S. private sector grew at a slightly faster pace than anticipated in September, marking a stark contrast between the healthy services sector and the struggling manufacturing industry, according to the flash estimates from the Purchasing Managers’ Index (PMI) report released by S&P Global on Monday. Despite better-than-expected readings for both the composite and services PMIs, two concerning trends emerged from September’s surveys. First, the manufacturing sector’ deepened contraction’s contraction deepened, with output levels hitting their lowest level since Decembe…