Maine’s unemployment rate continued its historic run reflected in January’s preliminary’s rate of 3.1 percent.

The state has seen unemployment rates of under 4 percent for more than four years now, and the rate has essentially remained unchanged for two years.

The rate, released by the Maine Department of Labor on Monday, was little changed from 3.0 percent for December and 3.2 percent one year ago. The number of unemployed was down 1,300 over the year to 21,200.

The data reflect an increase of 4,400 nonfarm jobs from a year ago to 639,700. Government jobs are up 400 from a year ago, reflecting gains at Portsmouth Naval Shipyard in Kittery. Other employment gains were noted in social assistance, health care and manufacturing, according to the department’s news release.

The U.S. unemployment rate of 3.6 percent for January was little changed from 3.5 percent for December and down from 4.0 percent one year ago. The New England estimate was 3.0 percent. Vermont had the lowest regional rate at 2.4 percent, followed by New Hampshire at 2.6 percent, Massachusetts at 2.8 percent, Rhode Island at 3.4 percent and Connecticut at 3.7 percent.