The approach

Work from usable time and the skills required. Separate effort from elapsed duration and allow for real operational commitments.

  1. Confirm the work, required skills and the planning period.
  2. Obtain usable availability from resource owners after leave and other commitments.
  3. Compare demand with capacity by skill and time window, then change sequencing, scope or staffing explicitly.

Worked example

Four people are each available for five days at six usable hours per day. Their nominal available effort is 4 × 5 × 6 = 120 person-hours. A specialist review still needs a qualified reviewer; total hours cannot remove that bottleneck.

Limits & next steps

Availability is not productivity, and people are not interchangeable. Parallel work, onboarding and coordination can change the elapsed duration.

Source & further reading

This explanation and worked example are independently written. The linked publication provides context for the technique; it is not a licence to reuse its material.

GAO: Cost Estimating and Assessment Guide

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