Table 7: System Operating Expenses (excluding Regional Jet Contract) per Aircraft,,,,,,,,
Passenger Airlines by Group,,,,,,,,
Ranked by 2006 Performance,,,,,,,,
(Cost in Millions of Dollars Excluding Regional Jet Contract Expenses per Aircraft) ,,,,,,,,
 2006 Rank ,,2001,2002,2003,2004,2005,2006,"Change
2001-2006"
1,Network ,24.818,23.041,22.540,25.198,27.161,29.409,4.591
2,Low-Cost ,15.404,14.967,15.332,16.765,18.049,19.144,3.740
,14-Carrier Average,23.232,21.560,21.076,23.312,24.992,26.709,3.477
,Group Dollar Difference,9.414,8.074,7.208,8.433,9.112,10.265,0.851
"Source: Bureau of Transportation Statistics, Form 41 Airline Financial Data ",,,,,,,,