WASHINGTON (AP) — U.S. employers dramatically stepped up hiring in December, adding 312,000 jobs in an encouraging display of strength for an economy in the midst of a trade war, slowing global growth and a partial government shutdown.

The Labor Department said Friday that the unemployment rate rose slightly to 3.9 percent, but that reflected a surge in job seekers — a positive for growth.

Average hourly pay improved 3.2 percent from a year ago, up from 2.7 percent at the end of 2017.

The jolt in hiring offered a dose of reassurance after a tumultuous few months on the financial markets.