If you use a CLASS statement to name classification variables, PROC SURVEYREG displays a “Class Level Information” table. This table contains the following information for each classification variable:
CLASS Variable, which lists each CLASS variable name
Levels, which is the number of values or levels of the classification variable
Values, which lists the values of the classification variable. The values are separated by a white space character; therefore, to avoid confusion, you should not include a white space character within a classification variable value.