When to use it
Use it to maintain a trustworthy boundary for cost and progress reporting.
When to be cautious
Counting added requirements without considering their size and value can mislead.
Apply it
Scope-item change = approved additions − approved removals
A count is meaningful only alongside size, complexity and acceptance changes. It is not a substitute for approved baseline control.
- Retain an agreed baseline and a change log.
- Trace additions, removals and acceptance changes to decisions.
- Reconcile schedule, cost and benefits with approved changes.
An example in practice
A requested integration is approved with funding and timing changes. Unrecorded additions remain visible until an authorised decision is made.
Source & credit
Standard estimating practice; the cited guide documents use rather than claiming invention.
GAO: Cost Estimating and Assessment Guide
This explanation and example are independently written. The source is a reading reference; linking it does not grant permission to reuse its text, figures or assessments.