An index value above 50 shows expansion in the manufacturing sector, while a value under 50 signals contraction.

Among the sub-indices that comprise the PMI, the production volume index fell. In the last 20 years there was only one occasion when the sub-index was lower than its current level.

The new orders index was also under the 50-point threshold and below the long running average measured since 1995 and also below the average of the previous three years.

Delivery times were longer than in November, the sub-index last stayed above the 50-point threshold in April 2015.

Purchased stocks were down in December after growing in November.

The employment index climbed back above 50 points in December.