Choose the unit before the formula
A delivery business might analyze an order. A subscription business might analyze a paid account per month and then follow an acquisition cohort over time. Both are useful, but they answer different questions. Write the unit, currency and period at the top of the worksheet.
The SEC introduction to financial statements helps distinguish revenue, expenses and cash flow. Unit economics are a management view built from defined inputs; they should not be presented as a substitute for complete financial statements.
Calculate contribution with a reproducible example
Consider a fictional order with $100 of revenue and $60 of directly variable costs. Contribution is $40, or 40% of revenue. Whether a particular cost belongs in the variable category depends on the business and the decision. State the allocation rather than hiding it.
| Illustrative order economics | USD per order |
|---|---|
| Revenue | $100 |
| Product and variable fulfillment cost | $60 |
| Contribution before acquisition and overhead | $40 |
The example is an original teaching calculation, dated September 10, 2026. It excludes fixed overhead, tax and acquisition costs. If acquiring a customer costs $80 and each repeat order produces the same $40 contribution, two orders recover that acquisition amount in this simplified model. They do not also recover every other company expense.
Keep lifetime assumptions separate from observations
Observed contribution from completed orders is different from predicted lifetime contribution. If a cohort is only two months old, a multi-year lifetime-value number is mostly a model. Show the observation period and the retention assumptions beside it.
Avoid comparing a revenue-based lifetime value with a contribution-based acquisition payback calculation. Use consistent boundaries. If refunds, support or infrastructure costs vary by customer segment, calculate those segments separately before drawing a company-wide conclusion.
Add cash timing and capacity
A profitable-looking order can still require cash before payment arrives. Record when suppliers, staff and platforms must be paid and when the customer pays. A growth plan can increase the funding requirement even when contribution per unit is positive.
Capacity is another boundary. A service may need a new employee or a larger platform plan after a volume threshold. Model that step instead of assuming all costs rise smoothly. The SaaS pricing guide shows how a plan change affects an operating estimate.
Use the CAC guide for acquisition definitions and the SBA planning resources for the broader business plan. Treat this worksheet as a way to expose assumptions, not as investment advice or a valuation.