U.S. manufacturing grew at a slightly slower pace in December but hiring hit a 2-1/2-year high and the volume of new orders soared to a level last seen in early 2010, an industry report showed on Thursday.

The Institute for Supply Management (ISM) said its index of national factory activity stood at 57.0 last month. That was in line with economists' forecasts but a touch below November's 2-1/2-year high of 57.3. Readings above 50 indicate expansion.

Even so, December's result was the second highest reading this year. The goods-producing sector contracted in May but its growth accelerated over the second half of 2013.

And the forward-looking new orders index, at 64.2, checked in at its highest level since April 2010, suggesting momentum in the sector could quicken in 2014. It stood at 63.6 in November.

The employment index rose to 56.9, its best showing since June 2011, from 56.5 in November.