Colorado unemployment rate jumped back above 3 percent in December, largely due to a surge of people rejoining the labor force, according to the Colorado Department of Labor and Employment. The state’s unemployment rate stood at 3.1 percent in December, up from 2.9 percent in November. It is above the 3 percent rate recorded in December of 2016 as well as the record low of 2.3 percent reached last spring, but below the U.S.