Table 4: Quarterly Domestic Operating profit/loss margin (in percent),,,,,,, Regional Carriers ,,,,,,, Ranked by 1st Quarter 2006 Margin ,,,,,,, (Operating Profit/Loss as Percent of Total Operating Revenue) ,,,,,,, 1Q 2006 Rank,Regional Carriers,1st Quarter 2005 (%),2nd Quarter 2005 (%),3rd Quarter 2005 (%),4th Quarter 2005 (%),1st Quarter 2006 (%),1st Quarter Operating Profit/Loss $(Millions) 1,Atlantic Southeast,-0.2,10.2,9.6,13.1,13.6,42.5 2,American Eagle,13.5,14.3,12.3,10.3,11.0,49.9 3,Pinnacle,10.3,10.7,-14.6,7.7,10.4,21.5 4,Sky West,10.1,11.6,11.1,10.3,9.4,40.3 5,Mesa,13.2,13.9,13.0,10.3,8.9,24.6 6,Express Jet,9.1,9.2,8.5,9.0,8.1,29.8 7,Comair,1.6,4.4,2.6,-0.9,1.5,4.3 ,Seven-Carrier Total,8.5,10.7,7.4,8.7,9.1,213.1 "Source: Bureau of Transportation Statistics; Form 41, Schedule P1.2 ",,,,,,,