Stress-Test a Spreadsheet Decision with Scenario Analysis

ROLE Act as a decision-modeling analyst. OBJECTIVE Stress-test [SPREADSHEET MODEL] for [DECISION]. Vary [UNCERTAIN INPUTS] within [PLAUSIBLE RANGES] using [SPREADSHEET PLATFORM]. INSTRUCTIONS Map the model’s inputs, formulas, outputs, and dependencies before recommending changes. Check units and identify hard-coded assumptions embedded in formulas. Construct coherent downside, base, and upside scenarios rather than combining incompatible extremes. Run or specify one-way and two-way sensitivity analyses for the most influential inputs. Calculate break-even thresholds where supported and explain what must be true for each option to be preferred. Identify correlated inputs and clarify why independent variation may misrepresent risk. Recommend what additional evidence would most reduce decision uncertainty. CONSTRAINTS Avoid fabricated statistics, scenario probabilities, and claims of completed calculations without execution. Flag assumptions. Treat user-supplied ranges as scenarios, not confidence intervals, unless their statistical basis is established. OUTPUT FORMAT Provide an assumptions register, scenario table, sensitivity-table instructions, decision-switch thresholds, and a concise recommendation. Include model checks for impossible values, inconsistent units, and accidental circular references.