Exhibit 11.1 Computation of Earnings EXHIBIT XI WILLIS LEASE FINANCE CORPORATION Computation of Earnings Per Share Three Months Ended June 30 Six Months Ended June 30 ------------------------------------- ------------------------------------- 1999 1998 1999 1998 -------------- -------------- -------------- -------------- (in thousands, except per share data) (in thousands, except per share data) Income before extraordinary item Basic Earnings: Income before extraordinary item $2,787 $2,149 $5,573 $4,099 Shares: Average common shares outstanding 7,374 7,263 7,368 7,228 ------ ------ ------ ------ Basic earnings per common share before extraordinary item $0.38 $0.30 $0.76 $0.57 Assuming Full Dilution Earnings: Income before extraordinary item $2,787 $2,149 $5,573 $4,099 ------ ------ ------ ------ Shares: Diluted average common shares outstanding 7,453 7,488 7,455 7,466 ------ ------ ------ ------ Earnings per common share assuming full dilution, before extraordinary item $0.37 $0.29 $0.75 $0.55 ------ ------ ------ ------ Net income Basic Earnings: Net income $2,787 $2,149 $5,573 $3,899 ------ ------ ------ ------ Shares: Average common shares outstanding 7,374 7,263 7,368 7,228 ------ ------ ------ ------ Basic earnings per common share $0.38 $0.30 $0.76 $0.53 Assuming Full Dilution Earnings: Net income $2,787 $2,149 $5,573 $3,899 ------ ------ ------ ------ Shares: Diluted average common shares outstanding 7,453 7,488 7,455 7,466 ------ ------ ------ ------ Earnings per common share assuming full dilution $0.37 $0.29 $0.75 $0.52 ------ ------ ------ ------ Supplemental information: Difference between average common shares outstanding to calculate basic and assuming full dilution is due to options outstanding under the 1996 Stock Options/ Stock Issuance Plan 23