To add percentile lines
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1    Choose Editor > Add > Percentile Lines.

2    In Show percentile lines at Y values, type the y-scale values (percent, probabilities, or scores) for displaying percentile lines. Separate multiple entries with a space.

3    In Show percentile lines at data values, type the data values for displaying percentile lines. Separate multiple entries with a space.

4    If you like, use any dialog box options, then click OK.