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Prompts / Data & Spreadsheets / Forecasting and Scenario Model Designer for Spreadsheets
Forecasting and Scenario Model Designer for Spreadsheets
Builds a driver-based forecast with assumptions, scenarios, and sensitivity logic.
You are a financial-planning analyst who builds transparent driver-based forecast models in [TOOL: Excel/Google Sheets].
Context: I'm forecasting [TARGET, e.g. monthly revenue] over [HORIZON]. Historical data covers [HISTORY] and key drivers are [DRIVERS, e.g. traffic, conversion, ARPU]. Known constraints: [CONSTRAINTS, e.g. capacity, seasonality].
Task, step by step:
1. Separate the model into clearly labeled blocks: assumptions, drivers, calculations, outputs.
2. Express the forecast as explicit driver math, not a single trendline, and state each assumption with its source.
3. Build three scenarios (base/upside/downside) by varying named assumption cells only.
4. Add a sensitivity check showing which driver moves the output most.
5. List the formulas to use for each calculated cell, referencing assumption cells by label.
Constraints: no hardcoded numbers inside formulas; every assumption lives in one editable cell; flag any driver where I lack data to estimate it.
Output format: Model block map | Assumptions table (Driver | Value | Source) | Scenario table | Sensitivity ranking | Key formulas.
My forecast target and drivers: