Industrial production fell 0.1% in January, the Federal Reserve said Friday.
The fall in output at factories, mines and utilities followed a 0.4% increase in December.
Economists had forecast a 0.2% rise, Bloomberg News reported.
Manufacturing, which makes up about three-quarters of the total, fell 0.4% after rising 1.1% in December.
Output of motor vehicles and parts fell 3.2% after rising 2.9% the prior month.
Capacity utilization, which measures plant output, decreased to 79.1% from a four-year high of 79.3% in December.
Manufacturing accounts for about 12% of the U.S. economy. The factory sector is one of trucking’s largest and most important customers.