The Austin-Round Rock area in Texas and the Denver-Aurora-Lakewood, Colo., area had the lowest unemployment rates in February, 3.1% each, 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 6.8% in February.

Among metropolitan areas of all sizes, Burlington-South Burlington, Vt., had the lowest unemployment rate in February at 2.6%. El Centro, Calif., had the highest unemployment rate at 18.6%.