Workers make brackets for Chevrolet Express Vans at VIA Motors in Orem, Utah.

Monthly jobs openings — a gauge of the U.S. economy that's closely watched by Fed chair Janet Yellen — were little changed in December, the Bureau of Labor Statistics said on Tuesday.

Monthly job openings were at 5.5 million on the last business day of December, according to the Bureau of Labor Statistics' Job Openings and Labor Turnover Summary (JOLTS).

That figure is in line with what economist expected, according to a consensus estimate from Thomson Reuters. Job openings were at 5.5 million in the previous month.