U.S. employers added 266,000 jobs in November, the U.S. Bureau of Labor Statistics reported earlier Friday. The number of people employed in manufacturing rose by 54,000 in November, after a decline in October when General Motors (GM) workers were on strike, the bureau said.

In a blog titled "Headline Employment Gains Mask Weakness," Swonk wrote that the manufacturing sector "actually appears to have lost jobs" after adjusting for the return of striking GM workers and those laid off because of idled production at GM.

According to an earlier report from the Institute for Supply Management, economic activity in the U.S. manufacturing sector contracted in November, the fourth month in a row, with the Purchasing Managers' Index standing at 48.1 percent.

The service sector continued to hold up significantly better than manufacturing, Swonk said, noting that nearly 40 percent of job gains during the month were in healthcare and social assistance, and leisure and hospitality.

"Job gains in the healthcare sector are being driven by aging baby boomers and a surge in the number of those who are over 80 years old," she said.

Retail hiring was essentially unchanged for the month but has fallen more than 30,000 over the last year, she said, adding that the shift from in-store to online shopping has triggered a surge in retail bankruptcies, which is holding down overall employment.

Overtime in the manufacturing sector fell during the month compared to a year ago, and that, according to Swonk, "reflects the ongoing weakness associated with tariffs and growth abroad."

The unemployment rate slid by 0.1 percentage points to 3.5 percent, the lowest since December 1969.

Job gains have averaged 180,000 per month so far in 2019, compared with an average monthly gain of 223,000 in 2018, indicating that the overall level of hiring has been slowing down over the past few months.