When to use it
Use explicit completion rules before reporting earned value or progress.
When to be cautious
Time spent and money spent are not reliable substitutes for completed scope.
Apply it
Weighted completion = Σ(milestone weight × completion credit) / Σ weights
Weights must be agreed before reporting. Credits need observable acceptance evidence; this is not a measure of time consumed.
- Define a deliverable and its acceptance evidence.
- Choose a consistent milestone, unit-count or completion-credit rule.
- Apply it at each status date and reconcile it with actual cost.
An example in practice
Credit a migrated system after the agreed validation has passed, not when the team has consumed its allocated hours.
Source & credit
Standard estimating practice; the cited guide documents use rather than claiming invention.
GAO: Cost Estimating and Assessment Guide
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