Graphs generated with the QQPLOT and PROBPLOT statements in PROC UNIVARIATE will be incorrect when the analysis variable has missing values.

To circumvent this problem, either use PROC CAPABILITY in SAS/QC Software or specify a WHERE statement to omit the missing values in PROC UNIVARIATE. For example:

  Where X is not missing;

if your analysis variable is called X. If a summary of missing values is also needed, then run PROC UNIVARIATE twice--once with and once without the missing values.