A company’s reported revenue is a single number. The Customer Cohort Test decomposes it into the behaviour of the customer groups that produced it, revealing whether the revenue is durable, expanding or quietly eroding beneath the surface.
The Cohort Methodology
Group customers by the year they were acquired. For each cohort, track revenue in each subsequent year.
Year 1 cohort (acquired FY22): Revenue in FY22: Rs 40 crore. FY23: Rs 38 crore. FY24: Rs 35 crore. FY25: Rs 32 crore. This cohort is contracting at approximately 7% per year. The customers acquired four years ago are spending less each year.
Year 2 cohort (acquired FY23): Revenue in FY23: Rs 25 crore. FY24: Rs 28 crore. FY25: Rs 30 crore. This cohort is expanding at approximately 9% per year. These customers are increasing their spend.
Year 3 cohort (acquired FY24): Revenue in FY24: Rs 30 crore. FY25: Rs 22 crore. This cohort contracted 27% in its second year, suggesting that the initial purchase was driven by a promotion or trial that did not convert to sustained purchasing.
The total revenue in FY25 is Rs 84 crore (32 + 30 + 22). The management presentation shows “stable revenue.” The cohort analysis shows a business whose older customers are churning, whose mid-vintage customers are growing and whose newest customers are not retaining. The aggregate masks three fundamentally different dynamics.
What the Cohort Test Reveals
Net revenue retention (NRR): Revenue from existing customers this year divided by revenue from the same customers last year. NRR above 100% means customers are spending more (expansion exceeds churn). NRR below 100% means they are spending less (churn exceeds expansion).
Gross churn rate: The percentage of prior-year revenue lost to customer departures. This is the revenue the company must replace through new acquisition before any growth occurs. A company with 15% gross churn must acquire 15% of its revenue base as new customers just to stay flat.
Cohort quality trajectory: Are more recent cohorts retaining better or worse than older ones? Improving cohort quality suggests the company is getting better at acquiring and retaining valuable customers. Deteriorating cohort quality suggests the opposite.
Customer acquisition cost vs lifetime value: What does it cost to acquire a customer in each cohort, and what is the cumulative revenue from that customer over subsequent years? If acquisition cost exceeds lifetime value for recent cohorts, the company is paying more to acquire customers than those customers will ever return.
In Northrop Management Private Limited’s commercial due diligence practice, the Customer Cohort Test is the analytical tool that converts a revenue figure into a revenue quality assessment.
Ashish Chaudhary, frames the analytical principle directly: “A revenue number becomes more valuable when its underlying customers become more predictable. The Customer Cohort Test reveals whether the company’s revenue is building on a strengthening foundation or growing on top of a weakening one. The aggregate number hides the answer. The cohort analysis reveals it.”
Questions for the Boardroom
- What is our NRR from existing customers, and is it above or below 100%?
- How does the retention of our most recent customer cohort compare to cohorts acquired two and three years ago?
- What is our gross churn rate, and how much new revenue must we acquire annually just to maintain the current base?
- For each customer cohort, does the lifetime revenue exceed the acquisition cost?
- If we projected our current cohort trends forward three years, would total revenue grow, stabilise or decline?
Closing Implication
Revenue is a number. Customer cohort behaviour is the story behind the number. A company whose cohorts are expanding and retaining has revenue that is durable and growing organically. A company whose cohorts are contracting and churning has revenue that must be continuously replaced through new acquisition, and the cost and effort of that replacement is the true cost of maintaining the business.
