Unit Economics and KPI Dashboards

The practical point: you want to know whether each customer or unit sold generates enough profit to cover acquisition costs and fund growth, and you can test that with LTV/CAC ratios, contribution margin per unit, and sector-specific KPIs that signal business health before earnings reports do.

Why Unit Economics Matter

Unit economics is not accounting theory; it is survival math. A company with $50 million in revenue can be worthless if customer acquisition costs exceed lifetime value, while a company with $8 million can be a compounding machine if each customer generates 3-5x their acquisition cost over time. The point is: you are not valuing revenue lines; you are valuing the profitability of each incremental customer or unit.

Why this matters: companies with LTV/CAC below 1.0x are burning cash on every customer they acquire--growth accelerates losses. Companies with LTV/CAC above 3.0x can reinvest profits into acquiring more customers, creating a compounding loop. The difference shows up in equity returns: SaaS companies with net revenue retention above 120% outperformed peers with NRR below 100% by 42% annualized over the 2015-2022 period (Bessemer Cloud Index data).

LTV/CAC: The Customer Profitability Gate

The calculation

LTV (Lifetime Value) = (Average Revenue per User) x (Gross Margin %) x (Customer Lifespan in years)

CAC (Customer Acquisition Cost) = (Total Sales + Marketing Spend) / (New Customers Acquired)

LTV/CAC Ratio = LTV / CAC

The thresholds you apply

Use a 4-tier decision framework:

• Unhealthy: <1.0x (you lose money on every customer; stop spending)
• Marginal: 1.0x-2.0x (breakeven zone; business model needs work)
• Healthy: 3.0x-5.0x (sustainable growth capacity; this is your target)
• Underleveraged: >5.0x (you may be underinvesting in growth)

The point is: 3.0x is not a guess; it allows ~33% of LTV for acquisition, ~33% for servicing costs, and ~33% for profit/reinvestment.

CAC Payback: The liquidity test

Even with 4.0x LTV/CAC, if payback takes 36 months, you need 3 years of cash runway per cohort before seeing returns. Calculate:

CAC Payback (months) = CAC / (Monthly Revenue per Customer x Gross Margin %)

Target: <12 months for healthy subscription businesses, <18 months for enterprise SaaS with longer sales cycles.

Contribution Margin Per Unit

Gross margin vs contribution margin

Gross margin = (Revenue - COGS) / Revenue

Contribution margin = (Revenue - Variable Costs) / Revenue

The difference: contribution margin includes all variable costs (payment processing, customer support per user, variable infrastructure), not just product costs. A SaaS company with 80% gross margin may have only 65% contribution margin after variable customer success costs.

Per-unit economics for physical goods

For retail or manufacturing, you calculate contribution margin per SKU:

• Selling price: $49.99
• COGS: $18.50 (63% gross margin)
• Variable shipping/fulfillment: $6.20
• Payment processing (2.9% + $0.30): $1.75
• Contribution margin: $23.54 (47.1% contribution margin)

Why this matters: if your marketing cost per unit sold exceeds $23.54, you are losing money on each sale regardless of what gross margin says.

Sector-Specific KPIs

SaaS: The growth quality metrics

The point is: NRR above 100% means existing customers grow faster than they leave--you can stop all new sales and still grow.

Retail: The operational efficiency metrics

Why this matters: a retailer with 12% same-store sales growth but declining inventory turns may be channel-stuffing or building obsolescence risk (see Bed Bath & Beyond's +8.4% inventory vs -7.3% revenue divergence before bankruptcy).

Building a KPI Dashboard

The minimum viable dashboard (5 metrics)

For any business model, track these weekly or monthly:

1. Revenue growth rate (trailing 12-month, to smooth seasonality)
2. Gross margin % (watch for >200 bps compression as a warning)
3. LTV/CAC or contribution margin per unit (the unit economics gate)
4. Cash runway in months (operating expenses / cash balance)
5. One sector-specific KPI (NRR for SaaS, SSS for retail, occupancy for REITs)

The signal hierarchy

Not all movements are equal. Prioritize signals in this order:

• Tier 1 (act immediately): LTV/CAC drops below 2.0x, NRR drops below 100%, cash runway drops below 6 months
• Tier 2 (investigate within 30 days): Gross margin compresses >300 bps, churn increases >50% vs prior period
• Tier 3 (monitor quarterly): Revenue growth decelerates, inventory turns decline >15%

Worked Example: Analyzing a SaaS Company

You are evaluating CloudMetrics Inc., a B2B SaaS company with the following disclosed data:

Step 1: Calculate LTV/CAC

• Average Contract Value (ACV): $24,000/year
• Gross Margin: 78%
• Average Customer Lifespan: 4.2 years (implied by ~24% annual churn)
• LTV: $24,000 x 0.78 x 4.2 = $78,624
• S&M Spend (TTM): $18.2 million
• New Customers (TTM): 412
• CAC: $18.2M / 412 = $44,175
• LTV/CAC: $78,624 / $44,175 = 1.78x

You classify: 1.78x sits in the marginal zone (1.0x-2.0x)--the business model works but lacks buffer.

Step 2: Calculate CAC Payback

• Monthly Revenue per Customer: $24,000 / 12 = $2,000
• Monthly Gross Profit: $2,000 x 0.78 = $1,560
• CAC Payback: $44,175 / $1,560 = 28.3 months

You flag: 28 months exceeds the 18-month enterprise target--capital intensity is high.

Step 3: Check NRR and Churn

• Starting ARR: $89.4 million
• Expansion ARR: $14.2 million
• Contraction ARR: $3.1 million
• Churned ARR: $8.9 million
• NRR: ($89.4M + $14.2M - $3.1M - $8.9M) / $89.4M = 102.4%

You interpret: 102.4% NRR is above 100% (existing customers net-expand), but below the 110% threshold for "good" retention.

Step 4: Build the signal summary

The durable lesson: CloudMetrics is not uninvestable, but unit economics suggest it needs either higher ACV, lower churn, or reduced S&M spend to reach the 3.0x LTV/CAC level where growth becomes self-funding.

Common Implementation Mistakes

1. You calculate LTV with revenue, not gross profit. If you use $24,000 ACV instead of $18,720 gross profit (78% margin), you overstate LTV by 28% and make a 1.78x business look like 2.28x. Fix: always multiply by gross margin before extending across customer lifespan.

2. You ignore cohort decay in churn calculations. If you report 5% monthly churn as an average but newer cohorts churn at 8% while legacy customers churn at 2%, your forward LTV is overstated. Fix: segment churn by cohort vintage and use the most recent 3-6 cohorts for LTV projections.

Implementation Checklist (tiered by ROI)

High ROI (do first; 20 minutes per company)

• Calculate LTV/CAC and classify into <1.0x / 1-2x / 3-5x / >5x buckets.
• Calculate CAC payback in months; flag >18 months for enterprise, >12 months for SMB.
• Identify the one sector-specific KPI (NRR, SSS, inventory turns) and benchmark against peers.

Medium ROI (do next; 30 minutes per company)

• Decompose gross margin into contribution margin by estimating variable costs beyond COGS.
• Track cohort-level churn if disclosed; flag divergence between old and new cohorts >3 percentage points.
• Compute gross margin return on investment for inventory-heavy businesses.

Lower ROI (finish; 45 minutes per company)

• Build a 5-metric dashboard with signal hierarchy and threshold alerts.
• Compare company KPIs against 3-5 direct competitors to establish relative position.
• Model sensitivity scenarios: what happens to LTV/CAC if churn increases 200 bps or CAC rises 20%?

The Durable Lesson

The durable lesson: unit economics and KPIs are the early warning system that financial statements cannot provide--a company can report 25% revenue growth while LTV/CAC deteriorates from 4.0x to 1.5x, and the income statement will not tell you until 4-8 quarters later when margins collapse. By tracking LTV/CAC above 3.0x, NRR above 110%, and CAC payback below 18 months, you identify sustainable growth before the market prices it in--and avoid growth traps before they destroy capital.