The Conference Board employment trends index rose to a reading of 109.02 in December from its reading of 108.19 in November. The December reading is also up 3.1 percent from the same month a year ago.

“After posting a significant increase in December, following an upward revision in November, the employment trends index is improving,” said Gad Levanon, director of Macroeconomic Research at The Conference Board. “However, if economic activity continues to expand slowly in the first half of 2013, it would be difficult for employers to maintain the current rate of job growth.”

This month’s employment trends index includes annual revisions to data.