Colorado’s unemployment rate in March stayed put at 3.9%, where it’s been since January, according to the latest report released Wednesday by the state Department of Labor and Unemployment. That’s lower than a year ago’s 4.2%, and better than the U.S. rate of 4.3% in March. But staying at 3.9% for three months hides other weaknesses in the state’s job market data, including that there are fewer adults in the labor force. An estimated 26,192 Co…