When the NORMALTEST and PNORMAL options are specified in an INSET statement for a COMPHISTOGRAM plot in PROC CAPABILITY, incorrect results for the Shapiro-Wilk W test statistic and its p-value are displayed in every cell except the last one. All cells of the comparative plot will incorrectly contain the statistics from the last cell. The Shapiro-Wilk test is only computed when there are less than or equal to 2000 observations in the analysis variable, and the W statistics and p-values are correct in both the printed output and the output data set.

To circumvent the problem, specify BY and HISTOGRAM statements instead of a COMPHISTOGRAM statement with the CLASS= option.