Republic announced this month that Midwest's name would go away over the next 12 to 18 months in favor of the other airline it bought last year, Frontier Airlines. According to the Bureau of Transportation Statistics, AirTran was the biggest carrier in Milwaukee during the 12 months ended Jan. 31: 24.0 percent, compared to 14.1 percent for Republic, 13.1 percent for SkyWest, 12.6 percent for Northwest and 7.6 percent for Midwest. That may be a little misleading, since Midwest was getting feed from Republic, SkyWest and Northwest, I believe. so the family of Midwest-center carriers probably carried more than AirTran. However, Midwest as a legal airline officially disappeared in November when Republic let its operating certificate expire. AirTran kept growing its market share during the period, and AirTran pegged it at 30 percent now. The numbers also don't reflect any presence for Southwest Airlines, which began service there in November.