1 EXHIBIT 11.1 DIAMOND OFFSHORE DRILLING, INC. STATEMENT RE COMPUTATION OF PER SHARE EARNINGS (IN THOUSANDS, EXCEPT PER SHARE DATA) THREE MONTHS ENDED SEPTEMBER 30, ----------------------------------------------------------------------------------- 1999 1998 ----------------------------------------- ---------------------------------------- WEIGHTED WEIGHTED AVERAGE PER SHARE AVERAGE PER SHARE INCOME SHARES AMOUNT INCOME SHARES AMOUNT (NUMERATOR) (DENOMINATOR) (NUMERATOR) (DENOMINATOR) ----------------------------------------- ---------------------------------------- BASIC EPS Net income .......................... $ 37,846 135,824 $ 0.28 $ 108,702 137,652 $ 0.79 EFFECT OF DILUTIVE POTENTIAL SHARES Convertible notes ................... 1,399 9,876 2,350 9,876 DILUTED EPS ----------------------------------------- ---------------------------------------- Net income + assumed conversions .... $ 39,245 145,700 $ 0.27 $ 111,052 147,528 $ 0.75 ========================================= ======================================== NINE MONTHS ENDED SEPTEMBER 30, ----------------------------------------------------------------------------------- 1999 1998 ----------------------------------------- ---------------------------------------- WEIGHTED WEIGHTED AVERAGE PER SHARE AVERAGE PER SHARE INCOME SHARES AMOUNT INCOME SHARES AMOUNT (NUMERATOR) (DENOMINATOR) (NUMERATOR) (DENOMINATOR) ----------------------------------------- ---------------------------------------- BASIC EPS Net income......................... $ 142,891 135,821 $ 1.05 $ 301,089 138,762 $ 2.17 EFFECT OF DILUTIVE POTENTIAL SHARES Convertible notes.................. 4,858 9,876 7,305 9,876 DILUTED EPS ----------------------------------------- ---------------------------------------- Net income + assumed conversions... $ 147,749 145,697 $ 1.01 $ 308,394 148,638 $ 2.07 ========================================= ========================================