The U.S. manufacturing sector expanded at its weakest pace in 15 months in December 2018 as growth in output and new orders slowed, the latest survey data from IHS Markit showed.
IHS Markit's U.S. manufacturing purchasing managers' index fell to 53.8 last month from 55.3 in November 2018. A reading above 50 indicates an overall monthly increase.
Order books grew at their slowest rates since September 2017, and business confidence among manufacturers dropped to its lowest level since October 2016, according to IHS Markit. The pace of job creation in the sector also eased to an 18-month low.
"Some of the weakness is due to capacity constraints, with producers again reporting widespread difficulties in finding suitable staff and sourcing sufficient quantities of inputs," said IHS Markit chief business economist Chris Williamson.
The latest survey data also showed signs of slower customer demand growth and rising concerns over the impact of tariffs, Williamson added.
Williamson said manufacturers are "less upbeat about prospects for 2019" and that the weaker monthly sector growth serves as "further evidence that companies have become increasingly cautious about spending amid rising uncertainty about the outlook."