“…The mean of that input for each DMU is given in Table1, the covariance matrix is randomly generated, and the efficiency scores are in Table2. The performances ofDMUs 1,2,3,4,6,7,8,10,11,12,14,15,18, 19,and 20 are not affected by the addition of this variable. While DMUs 9, 13, 16, and 17 performances are extremely affected by this variable, they become efficient in all cases.…”