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.

• If "Include sub-items into calculation" turned on then task estimates and their quantity will be taken into account while calculating metrics (it mostly affects affects Productivity  & Scope and Backlog metrics).

• If "Include sub-items into calculation" turned off then tasks are not included into the calculation in items at all but estimates are summarized in most most Productivity metrics.

To including/excluding sub-items in calculation go to Project Configuration → Task Tracking Systems (Jira, Rally, TFS/VSTS) → Workflow.

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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 bucketsDiagram (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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