Hi @JZ,
Welcome in the Community !
In order to solve this problem, you can try to add in your "Group" column a "Value Order" property.
To do this, right-click in your "Group" column name, click on "Column Properties" and then "Value Order" :
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You can then in the new window indicate the order of the categories :
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And this ordering will be kept in the graph builder :
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Hope this answer will help you,
Victor GUILLER
"It is not unusual for a well-designed experiment to analyze itself" (Box, Hunter and Hunter)