PERF allows to include and exclude sub-items from metrics calculation. This can be helpful if you need calculate metrics for a project duration/release and sub-items estimation and quantity is no object in this case.

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Include sub items checkbox affects calculation in the following metrics:

• Backlog Health
• Ready for Development
• Sprint Scope Stability
• Velocity by week/month
• Velocity by week (non-defects)
• Average Velocity
• Velocity: Committed vs. Completed
• Commitment Rate
• Iteration Scope Conversion (depends on units of measure: if unit of measure is Items then sub-items are calculated only when "Include sub-items into metric calculation" is turned-on. If metric is in Story Points or Hours then Story Point and Hours are calculated regardless of "Include sub-items into calculation" check-box)
  
• Iteration Completion Snapshot (depends on units of measure: if unit of measure is Items then sub-items are calculated only when "Include sub-items into metric calculation" is turned-on. If metric is in Story Points or Hours then Story Point and Hours are calculated regardless of "Include sub-items into calculation" check-box)
• "Not Done" Bucket Review (depends on units of measure: if unit of measure is Items then sub-items are calculated only when "Include sub-items into metric calculation" is turned-on. If metric is in Story Points or Hours then Story Point and Hours are calculated regardless of "Include sub-items into calculation" check-box)
  
• Created vs Resolved
• Open Issue Aging
• Throughput
• Time in Status
• First Time Right
• Delivery Forecast via Burn-up(depends on units of measure: if unit of measure is Items then sub-items are calculated only when "Include sub-items into metric calculation" is turned-on. If metric is in Story Points or Hours then Story Point and Hours are calculated regardless of "Include sub-items into calculation" check-box)
• Cumulative Flow by status buckets (depends on units of measure: if unit of measure is Items then sub-items are calculated only when "Include sub-items into metric calculation" is turned-on. If metric is in Story Points or Hours then Story Point and Hours are calculated regardless of "Include sub-items into calculation" check-box)
  
• Cumulative Flow by workflow statuses()

Example if Include sub items checkbox affects calculation:

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