Unit Economics Analysis
description: Analyze unit economics for PE targets — ARR cohorts,
LTV/CAC, net retention, payback periods, revenue quality, and margin
waterfall. Essential for software/SaaS, recurring revenue, and
subscription businesses. Use when evaluating revenue quality, building a
cohort analysis, or assessing customer economics. Triggers on "unit
economics", "cohort analysis", "ARR analysis", "LTV CAC", "net
retention", "revenue quality", or "customer economics".
Workflow
Step 1: Identify Business
Model
Determine the revenue model to tailor the analysis:
- SaaS / Subscription: ARR, net retention,
cohorts
- Recurring services: Contract value, renewal rates,
upsell
- Transaction / usage-based: Revenue per transaction,
volume trends, take rate
- Hybrid: Break down by revenue stream
Step 2: Core Metrics
ARR / Revenue Quality
- ARR bridge: Beginning ARR → New → Expansion →
Contraction → Churn → Ending ARR
- ARR by cohort: Vintage analysis — how does each
annual cohort retain and grow?
- Revenue concentration: Top 10/20/50 customers as %
of total
- Revenue by type: Recurring vs. non-recurring vs.
professional services
- Contract structure: ACV distribution, multi-year %,
auto-renewal %
Customer Economics
- CAC (Customer Acquisition Cost): Total S&M
spend / new customers acquired
- LTV (Lifetime Value): (ARPU × Gross Margin) / Churn
Rate
- LTV:CAC ratio: Target >3x for healthy
businesses
- CAC payback period: Months to recover acquisition
cost
- Blended vs. segmented: Break down by customer
segment (enterprise vs. SMB vs. mid-market)
Retention & Expansion
- Gross retention: % of beginning ARR retained
(excludes expansion)
- Net retention (NDR): % of beginning ARR retained
including expansion
- Logo churn: % of customers lost
- Dollar churn: % of revenue lost (often different
from logo churn)
- Expansion rate: Upsell + cross-sell as % of
beginning ARR
Cohort Analysis
Build a cohort matrix showing:
| Cohort |
Year 0 |
Year 1 |
Year 2 |
Year 3 |
Year 4 |
| 2020 |
$1.0M |
$1.1M |
$1.2M |
$1.1M |
|
| 2021 |
$1.5M |
$1.7M |
$1.8M |
|
|
| 2022 |
$2.0M |
$2.3M |
|
|
|
| 2023 |
$3.0M |
|
|
|
|
Show both absolute $ and indexed (Year 0 = 100%) views.
Margin Waterfall
- Revenue → Gross Profit → Contribution Margin → EBITDA
- Fully loaded unit economics: what does it cost to acquire, serve,
and retain a customer?
- Gross margin by revenue stream (subscription vs. services vs.
other)
Step 3: Benchmarking
Compare unit economics to relevant benchmarks:
- SaaS Rule of 40: Growth rate + EBITDA margin >
40%
- SaaS Magic Number: Net new ARR / prior period
S&M spend > 0.75x
- NDR benchmarks: Best-in-class >120%, good
>110%, concerning <100%
- LTV:CAC: Best-in-class >5x, good >3x,
concerning <2x
- Gross retention: Best-in-class >95%, good
>90%, concerning <85%
- CAC payback: Best-in-class <12mo, good <18mo,
concerning >24mo
Step 4: Revenue Quality Score
Synthesize into a revenue quality assessment:
| Factor |
Score (1-5) |
Notes |
| Recurring % |
|
|
| Net retention |
|
|
| Customer concentration |
|
|
| Cohort stability |
|
|
| Growth durability |
|
|
| Margin profile |
|
|
| Overall |
|
|
Step 5: Output
- Excel workbook with ARR bridge, cohort matrix, unit economics
dashboard
- Summary slide with key metrics and benchmarks
- Red flags and areas for further diligence
Important Notes
- Always ask for raw customer-level data if available — aggregate
metrics can hide problems
- NDR above 100% can mask high gross churn if expansion is strong
enough — always show both
- Cohort analysis is the single most important view for revenue
quality — push for this data
- Differentiate between contracted ARR and actual recognized
revenue
- For usage-based models, focus on consumption trends and expansion
patterns rather than traditional ARR metrics
- Professional services revenue should be evaluated separately — it's
not recurring and margins are typically lower