cohort-chartslisted

# Cohort charts A cohort chart answers whether the business is getting better at keeping customers — which a single blended retention number cannot, because blended retention mixes a good recent cohort with a bad old one and reports the average. --- ## Construction rules — get these wrong and the chart lies **Fixed denominator.** Measure each cohort against **its own starting population**, tracked forward. Measuring against a moving denominator that includes new customers dilutes churn and makes retention look better than it is. This is the most common way cohort retention gets overstated. **One cohort assignment, forever.** A customer belongs to the cohort of their first period and never moves. Reassigning on upgrade or reactivation destroys comparability. **Logo and revenue are different charts.** Never mix them on one grid. Logo retention counts customers; revenue retention counts dollars and can exceed 100% through expansion. Show both — the divergence is the insight. High logo churn with low revenue churn means you are losing small customers, which is a go-to-market signal rather than a product crisis. **Define reactivation explicitly.** A customer who lapses and returns is either new or resumed, and that is a decision you record, not one you leave implicit. --- ## The triangle heatmap Rows are cohorts, columns are periods since acquisition. The characteristic staircase comes from recent cohorts having fewer periods of history. ``` Cohort n M0 M1