Scenario Planning and Sensitivity Analysis: Modeling Different Futures

Building Scenario Models

Scenario planning creates multiple forecasts to show range of possible outcomes. **Three-Scenario Framework** Conservative (20% probability, downside risk): - Lower growth (60% of base case growth) - Higher churn (current + 1%) - Higher CAC (current × 1.2) - Result: Slower expansion, more cash burn Base Case (60% probability, most likely): - Expected growth (based on current trajectory) - Current churn trends - Current CAC and payback - Result: What you expect to achieve Upside Case (20% probability, opportunity): - Faster growth (140% of base case) - Lower churn (current − 1%) - Lower CAC (current × 0.8) - Result: Accelerated expansion, strong profitability **Example Scenario Model** SaaS company, 3-year forecast: BASE CASE (Most likely): Year 1: - Starting ARR: £5M - Growth rate: 40% (from current pipeline, sales efficiency) - Ending ARR: £7M Year 2: - Starting ARR: £7M - Growth rate: 35% (market maturation, larger base) - Ending ARR: £9.45M Year 3: - Starting ARR: £9.45M - Growth rate: 25% (even larger base, market saturation) - Ending ARR: £11.8M Unit Economics (Base): - CAC: £8K (current) - Payback: 9 months (current) - Churn: 3% monthly (current) Profitability (Base): - Year 1: -20% operating margin (investment phase) - Year 2: -5% operating margin (approaching breakeven) - Year 3: +10% operating margin (profitable) CONSERVATIVE CASE (Downside risk): Year 1: - Starting ARR: £5M - Growth rate: 24% (60% of base 40%, slower adoption) - Ending ARR: £6.2M Year 2: - Starting ARR: £6.2M - Growth rate: 21% (60% of base 35%) - Ending ARR: £7.5M Year 3: - Starting ARR: £7.5M - Growth rate: 15% (60% of base 25%) - Ending ARR: £8.6M Unit Economics (Conservative): - CAC: £9.6K (+20% higher, harder to acquire customers) - Payback: 11 months (+2 months, slower) - Churn: 4% monthly (+1%, customer retention issues) Profitability (Conservative): - Year 1: -40% operating margin (slower growth, higher costs) - Year 2: -30% operating margin (still in investment mode) - Year 3: -10% operating margin (struggles to profitability) UPSIDE CASE (Opportunity): Year 1: - Starting ARR: £5M - Growth rate: 56% (140% of base 40%, strong adoption) - Ending ARR: £7.8M Year 2: - Starting ARR: £7.8M - Growth rate: 49% (140% of base 35%) - Ending ARR: £11.6M Year 3: - Starting ARR: £11.6M - Growth rate: 35% (140% of base 25%, market expands) - Ending ARR: £15.7M Unit Economics (Upside): - CAC: £6.4K (20% lower, efficient customer acquisition) - Payback: 7 months (2 months faster) - Churn: 2% monthly (1% lower, strong product-market fit) Profitability (Upside): - Year 1: 0% operating margin (growth investments, but profitable) - Year 2: +20% operating margin (clear path to profitability) - Year 3: +35% operating margin (highly profitable, scale) **Why Three Scenarios Matter** Board decision-making: Conservative case answers: "What's our downside if things don't go as planned?" - Helps determine cash runway, fundraising need - Shows risks to manage Base case answers: "What should we plan for?" - Guides hiring, spending decisions - Aligns team on targets Upside case answers: "What's our opportunity if execution is exceptional?" - Motivates team with potential - Shows path to significant exit value Example impact on fundraising decision: Conservative case: ARR £8.6M by year 3, operating margin -10% - Conclusion: Need additional funding, not clear path to profitability Base case: ARR £11.8M by year 3, operating margin +10% - Conclusion: Can be profitable with current capital, minimal additional raise needed Upside case: ARR £15.7M by year 3, operating margin +35% - Conclusion: Strong opportunity, can fundraise at premium to show board investors upside The board uses all three to make capital decisions. **Sensitivity Analysis** Sensitivity analysis tests how sensitive your forecast is to changes in key assumptions. Example: Base case forecast shows £11.8M ARR year 3. Key assumptions: - Growth rate 40% → 35% → 25% - CAC £8K - Churn 3% - Payback 9 months Test each assumption: Growth Rate Sensitivity: - If growth 40% (base) → Year 3 ARR: £11.8M - If growth 35% (−5%) → Year 3 ARR: £10.4M (−12%) - If growth 45% (+5%) → Year 3 ARR: £13.5M (+14%) Impact: 1% growth change = ~2% ARR impact (moderate sensitivity) CAC Sensitivity: - If CAC £8K (base) → Year 3 ARR: £11.8M (payback 9 months) - If CAC £9.6K (+20%) → Year 3 ARR: £9.2M (payback 11 months, more expensive to acquire) - If CAC £6.4K (−20%) → Year 3 ARR: £14.2M (payback 7 months, efficient acquisition) Impact: 20% CAC change = ~20% ARR impact (high sensitivity, very important) Churn Sensitivity: - If churn 3% (base) → Year 3 ARR: £11.8M - If churn 4% (+1%) → Year 3 ARR: £9.1M (−23%) - If churn 2% (−1%) → Year 3 ARR: £15.2M (+29%) Impact: 1% churn change = ~25% ARR impact (very high sensitivity, critical) Payback Sensitivity: - If payback 9 months (base) → Year 3 cash position healthy - If payback 12 months (+3) → Cash consumed faster, runway concern - If payback 6 months (−3) → Cash generated faster, funding not needed Impact: Payback affects cash runway significantly Pricing Sensitivity: - If increase price 15% → ARPU increases, revenue higher, same customers - If decrease price 15% → Grow faster, lower ASP but more volume Impact: Depends on price elasticity (how demand changes with price) **Tornado Diagram (Sensitivity Visualization)** A tornado diagram shows which assumptions matter most: Example (ranked by sensitivity impact): Assumption | Impact on Year 3 ARR − Churn (±1%) | ±£2.7M (23%) − CAC (±20%) | ±£2.4M (20%) − Growth rate (±5%) | ±£1.7M (14%) − Payback (±3 months) | ±£1.2M (10%, indirect via cash) − Pricing (±15%) | ±£1M (8%) Visualization: ← Downside | Base | Upside → Churn [←←←←←]┃[→→→→→] CAC [←←←←]┃[→→→→] Growth rate [←←←]┃[→→→] Payback [←←]┃[→→] Pricing [←]┃[→] The wider the bar, the more sensitive the outcome is to that assumption. Action: Focus management attention on wide-bar items (churn, CAC, growth). **Using Sensitivity for Decision-Making** Example: Decision on pricing strategy Current pricing: £5K/month Option A: Increase to £5.75K/month (+15%) - ARPU increases 15% - Assume demand decreases 10% (some customers don't upgrade) - Net revenue impact: +15% − 10% = +5% Option B: Decrease to £4.25K/month (−15%) - ARPU decreases 15% - Assume demand increases 30% (more customers sign up) - Net revenue impact: −15% + 30% = +15% Option B has higher revenue impact (15% vs 5%), so lower price is better if demand elastic (price-sensitive). But need to model: - Does lower CAC in Option B (more volume, better acquisition efficiency)? - Does higher churn in Option B (lower-value customers)? - What's the customer lifetime value in each case? Sensitivity analysis reveals these trade-offs. **Three-Year Financial Projection Template** Base case model (monthly year 1, quarterly year 2-3): Revenue: - New logos: [# customers] × [ASP] - Expansion revenue: [existing customers] × [ARPU increase] - Churn impact: [lost ARR from churn] - Total revenue Operating expenses: - COGS (scales with revenue) - S&M (acquisition, customer success) - R&D (product development) - G&A (overhead) - Total opex Profitability: - Gross margin - Operating margin - Cash runway (if not profitable) Key metrics: - ARR - Customer count - NRR - CAC - Payback Then build conservative and upside cases with 60%/140% adjustments. **Updating Scenarios Quarterly** Don't build scenarios once and forget them. Update quarterly: Q1 actual results: - Actual growth: 38% (vs. base 40%, close) - Actual CAC: £8.2K (vs. base £8K, slightly higher) - Actual churn: 2.8% (vs. base 3%, better) Update three scenarios with new actual data points: Base case: Was 40% growth, now revise to 38% (based on Q1 actual trend) Conservative: Was 24% growth, now revise to 23% (tracking actual) Upside: Was 56% growth, now revise to 53% (still ambitious but adjusted) This rolling update keeps scenarios grounded in reality while maintaining forward-looking planning. **Board Presentation of Scenarios** Don't just present base case. Show all three: Slide: "Three-Year Scenarios" | Metric | Conservative | Base | Upside | |--------|-------------|------|--------| | Year 3 ARR | £8.6M | £11.8M | £15.7M | | Year 3 Growth | 15% | 25% | 35% | | Year 3 Op Margin | -10% | +10% | +35% | | Year 3 Customers | 400 | 550 | 750 | | Probability | 20% | 60% | 20% | Narrative: "Our base case assumes 40% year 1 growth moderating to 25% by year 3, reaching £11.8M ARR. We believe this is 60% likely given current trajectory. Conservative case (20% probability) assumes slower growth (24-40% lower) and higher churn, reaching £8.6M ARR and operating margin of -10%. This is our downside if market adoption slower than expected. Upside case (20% probability) assumes faster growth (140% of base) and improved unit economics, reaching £15.7M ARR and +35% operating margin. This is possible if we achieve exceptional product-market fit and scale efficiently. We're planning for base case but have mitigation strategies for conservative outcome (cost controls) and execution plans for upside opportunity (hiring, marketing investment)." Scenarios show you've thought through risks and opportunities, not just blindly forecast one number.