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Unresolved Bugs Older Than a Month (top priorities) is measured as a number of items an amount of top priority issues with status is not closed.
where,
issue type = is Bug,
status of issues is not Closed,
top priority is Blocker or/and Critical ,(Top priority defect is a defect of a priority defined in Project Settings > Task Tracking system (Jira/TFS) > Quality management. )
Creation Date is older than 'current date minus 30 days.
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