You can get the sum column's time data by grouping statuses.
This Status Groups function is available for the following reports:
Time in Status
Average Time
Status Count
Time in Status per Date
To get the sum, go to the Status Groups. Here, you can:
create a new group (+Add New Group),
manage (edit or delete) existing groups.
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Add a name to your custom column and select statuses you want to group.
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As a result, you'll get one column with summed data from your previously selected columns.
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