Economists expect that Friday's jobs report will show job gains of 160,000 in December, with the unemployment rate holding steady at 3.5%, according to the data provider FactSet.

But key in the report will be whether the decade-plus expansion causes average hourly earnings to climb above the 3.1% annual gain seen in November as employers find themselves paying more to attract workers.

"We look for another strong gain in payrolls in December, although not as strong as November's 266,000 surge," said Rubeela Farooqi, chief U.S. economist at High Frequency Economics. The jump in hiring in November was aided by the end of a strike by workers at General Motors that caused the number of manufacturing jobs to climb by 54,000.

Expectations for the employment report were amplified by a report Wednesday from payroll processor ADP that showed private companies added 202,000 jobs in December. Still, the ADP report often varies from the government's more comprehensive surveys.

U.S. employers added 1.98 million jobs through the first 11 months of 2019. That's a solid number, although hiring may slow because the number of unemployed people seeking work has fallen to 5.8 million, the lowest level since 2000. With fewer unemployed people hunting for jobs, hiring might slow organically.

The steady hiring growth during the expansion has contributed to gains in consumer spending. Retail sales during the crucial holiday shopping improved 3.4% compared to the prior year, according to Mastercard SpendingPulse.

But online shopping accounted for much of that increase as e-commerce sales rose nearly 19%. Retailers have shed roughly 30,000 jobs in the 12-month period that ended in November because of this shift.

Manufacturing struggled last year because of trade tensions between the United States and China coupled with slower global economic growth. Hiring in the sector has declined as a result.