Table 9. Airline Domestic Unit Costs (Cents per Mile),,,,,,, Passenger Airlines by Group ,,,,,,, Ranked by 1st Quarter 2005 Domestic Unit Costs ,,,,,,, (Domestic Operating Expenses per Available Seat Mile in cents),,,,,,, 1Q 2005 Rank,,1st Quarter 2004,2nd Quarter 2004 ,3rd Quarter 2004 ,4th Quarter 2004 ,1st Quarter 2005 ,1st Quarter Operating Expense $(Millions) 1,Regional Carriers,13.0,12.5,12.6,13.1,13.3,"1,908.8" 2,Network Carriers,12.6,12.4,12.6,13.7,13.2,"15,365.4" 3,Low Cost Carriers ,7.7,7.9,7.8,8.8,8.8,"3,746.7" ,21-Carrier Total,11.4,11.3,11.4,12.4,12.1,"21,020.9" "Source: Bureau of Transportation Statistics; Form 41, Schedule P1.2. T100; T2 Data",,,,,,,