Ring-fence a contingency before allocating the launch envelope
A contingency that exists only on a slide can disappear as soon as campaign budgets are entered. A reproducible illustrative example with editable inputs and explicit limits.
A contingency that exists only on a slide can disappear as soon as campaign budgets are entered. This worksheet separates the reserved fraction from money available for planned activity. The reserve is an explicit scenario assumption, not an industry standard or a forecast of losses.
Define the calculation before using it
Start with the approved envelope and choose the fraction held back for specified events. Subtract it before allocating routine commitments. Document which events permit its release and who can approve that change; otherwise the same funds can be counted as both scheduled spend and emergency capacity.
Work through the synthetic example
A 50,000-unit envelope with a 15% reserve leaves 42,500 for planned commitments and 7,500 held back. A larger reserve is not automatically safer if the remaining test cannot answer its question. The sensitivity view makes the trade-off visible instead of treating reserve size as a virtue by itself.
| Output | Worked-example result |
|---|---|
| Reserved amount | 7500.0000 |
| Available for commitments | 42500.0000 |
Use the artifact and preserve its assumptions
Open the editable calculator to change the inputs and inspect the sensitivity view. The CSV records synthetic inputs and expected outputs; the JSON fixture keeps the equations available for reproduction. These calculations have been checked against the stated example. No measured campaign data is included.
The sensitivity rows vary only reserve by 20% below and above the entered value. They are scenarios, not confidence limits or a forecast distribution. A row outside the model’s constraints is labelled rather than turned into a plausible-looking result. Save the chosen inputs with the decision so another reader can distinguish a changed assumption from a changed formula.
Evidence and limits
Google distinguishes average daily budgets from campaign total budgets. This planning worksheet does not itself set a platform limit; verify the campaign’s actual budget mechanism before translating a plan into account settings. See Budgets overview, especially “Average daily budgets and spending limits; Other types of budgets”.
The model does not estimate incident probability or rework cost. It records an allocation rule; actual release decisions require evidence and an accountable owner.
Background: Annual and quarterly UA budget planning and A Q4 UA Budget Planning Checklist Before the Rush. These existing articles provide context; the present calculation does not verify every archived claim.
