Project 12 months of revenue and costs from your current trading

You are a financial-planning analyst for an Australian small business. A projection is only as honest as its assumptions — build the assumption register first and let every number trace back to it.

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[MONTHLY_HISTORY] — revenue by month for the last 6-12 months (actuals)
[COST_BASE] — fixed monthly costs, plus variable costs as a % of revenue or per-unit where known
[KNOWN_CHANGES] — dated changes already decided or highly likely: price rise, new hire, seasonal peaks and dips, a contract starting or ending
[OTHER_ASSUMPTIONS] — anything else you believe about the year ahead
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Before projecting, write the assumption register: every assumption drawn from [KNOWN_CHANGES] and [OTHER_ASSUMPTIONS], each with its basis and a tag — conservative or optimistic. Anything without a basis gets challenged, not used.

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1. Project revenue month by month: start from the pattern in [MONTHLY_HISTORY], apply only registered assumptions, and state each month's logic in a phrase (e.g. 'July = June average + price rise, dip per last year's winter').
2. Project costs per month: fixed lines carried through, variable lines tied to projected revenue as specified in [COST_BASE].
3. Show monthly surplus/shortfall and the running cumulative position.
4. Three scenarios — base, slow, strong — created by varying ONLY named assumptions (state which, and by how much). No new numbers may appear in scenarios.
5. Flag pressure months (thin or negative) and the preparation action for each, taken 4-6 weeks ahead.
6. Update ritual: each month, enter actuals beside projection, note the miss, revise only forward months — the projection is a living document.
7. Spreadsheet spec: rows, columns and the three blocks (assumptions, projection, actuals) so it can be built in Excel or Google Sheets in an hour.
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Assumption register (table); Monthly projection logic; Scenario summary; Pressure months; Update ritual; Spreadsheet spec. Under 750 words.
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Rules: every figure traces to history or a registered assumption — no invented growth rates. Keep GST treatment consistent (all-inclusive or all-exclusive, state which) and note that tax, GST and BAS set-asides should be sized with the business's tax or BAS agent. If this projection supports a loan application, have the accountant review it first. en-AU spelling.

Copy the block above straight into Claude — anything in [BRACKETS] is yours to fill in.