finance
Installation
SKILL.md
Finance — Unit Economics & Financial Models
Know your numbers. Every dollar in, every dollar out, every dollar you'll need.
Unit Economics
| Metric | Formula | Healthy Range |
|---|---|---|
| CAC | Total acquisition spend / new customers | Depends on LTV |
| LTV | ARPU × gross margin × avg lifespan (months) | LTV > 3× CAC |
| LTV:CAC | LTV / CAC | 3:1 to 5:1 |
| Payback period | CAC / (ARPU × gross margin) | < 12 months |
| Gross margin | (Revenue - COGS) / Revenue | > 70% for SaaS |
| Net revenue retention | (Start MRR + expansion - contraction - churn) / Start MRR | > 100% |
| Burn multiple | Net burn / net new ARR | < 2× good, < 1× great |