The categories of a Pareto chart are always determined using formatted values of the process variable, and the format is used to label the categories.
On the chart, the categories are displayed in decreasing order of frequency. If there are multiple categories with the same count, the tied categories are displayed in order of their formatted values.
When you create a comparative Pareto chart, the formatted levels of the CLASS= variables are used to group the data into cells. There is a cell for each level of the CLASS= variable in a one-way comparative chart, and there is a cell for each combination of levels of the CLASS= variables in a two-way comparative chart.
You can specify the order of the rows and columns corresponding to the classification levels with the ORDER1= and ORDER2= options. The default value of these options is INTERNAL, which means that the order is determined by the internal values of the CLASS= variables. It is possible for a particular formatted value to correspond to more than one internal value. To resolve this ambiguity, the internal value that determines the position of the row or column is the value that occurs first in the input data set.
Other values that you can specify for the ORDER1= and ORDER2= options are FORMATTED, FREQ, and DATA.