Stat > DOE > Display Design > Columns Not to Reorder
Use to specify columns in the worksheet that you do not want to be reordered according to standard or run order. By default, Minitab sorts a column if the number of rows is less than or equal to the number of rows in the design. For columns with fewer rows than the design, Minitab enters missing value symbols (*) in the empty cells. Minitab does not reorder columns that have more rows than the design.
Do not reorder the following columns: Enter columns that you do not want Minitab to reorder. You can only enter columns not included in the design.