Alaska Air Group, Inc. EXHIBIT 11 Computation of Earnings Per Common Share (In thousands, except per share) Three Months Ended Nine Months Ended September 30, September 30, 1997 1996 1997 1996 PRIMARY - Net income $42,200 $32,816 $57,300 $43,611 Average number of shares outstanding 14,671 14,467 14,580 14,165 Assumed exercise of stock options reduced by the number of shares purchased with the proceeds from exercise of such options 128 121 123 110 Average shares as adjusted 14,799 14,588 14,703 14,275 Primary earnings per common share $2.85 $2.25 $3.90 $3.06 FULLY DILUTED - Net income $42,200 $32,816 $57,300 $43,611 After tax interest on convertible debt 1,910 2,038 5,667 6,070 Income applicable to common shares $44,110 $34,854 $62,967 $49,681 Average number of shares outstanding 14,671 14,467 14,580 14,165 Assumed exercise of stock options 217 121 302 110 Assumed conversion of 6.5% debentures 6,151 6,151 6,151 6,151 Assumed conversion of 7.75% debentures 0 381 0 381 Assumed conversion of 6.875% debentures 1,608 1,608 1,608 1,608 Average shares as adjusted 22,647 22,728 22,641 22,415 Fully diluted earnings per common share $1.95 $1.53 $2.78 $2.22