Create the numeric informat Evaluation. The INVALUE statement
converts the specified values. The letters O
(Outstanding), S (Superior), E (Excellent), C (Commendable),
and N (None) correspond to the numbers 4, 3,
2, 1, and 0, respectively.
invalue evaluation 'O'=4
'S'=3
'E'=2
'C'=1
'N'=0;
run;