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When you add a new one, write down a name to your custom column and add necessary users to a group.
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After creating the User Group, remember to click the Save button in the Column Manager menu. Otherwise, the User Group will not be saved.
And, if you create the User Group in Presets, you also need to re-save the Preset to save the changes you made. More details.
As a result, you'll get one column with summed data from your previously selected columns.
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