The Austin-Round Rock area in Texas had the lowest unemployment rates in March, 3.1%, among US metropolitan areas with populations of 1 million or more, the US Bureau of Labor Statistics reported today.

The Chicago-Naperville-Elgin, Ill.-Ind.-Wis., metropolitan area posted the highest jobless rate among large metro areas at 6.6% in March.

Among metropolitan areas of all sizes, Ames, Iowa, and Sioux Falls, SD, had the lowest unemployment rates in March at 2.4% each. El Centro, Calif., had the highest unemployment rate at 18.6%; however, El Centro and Yuma, Ariz., had the largest year-over-year unemployment rate decreases in March, down 4.1% each.