Aggregate metrics lie by omission. A program showing 12% month-over-month revenue growth might be masking the fact that partners recruited six months ago are declining while a single new partner is carrying all the growth. Cohort analysis fixes this by grouping partners -- or referred customers -- by the time they joined, then tracking their behavior over time. It is the difference between knowing your average and knowing your trajectory.
Partner Cohorts vs Customer Cohorts
There are two types of cohort analysis in affiliate programs. Partner cohorts group affiliates by their activation month and track metrics like revenue per partner, conversion rate, and churn over time. Customer cohorts group the end users referred by affiliates and track their deposit frequency, trading volume, or purchase behavior over time. Both are valuable, but they answer different questions. Partner cohorts tell you whether your recruitment is improving. Customer cohorts tell you whether your partners are sending higher-quality traffic.
Cohort Type
Grouped By
Key Metrics
What It Reveals
Partner cohort
Month partner was activated
Revenue per partner, active rate, churn
Whether newer partners outperform older ones
Customer cohort
Month customer was referred
LTV, deposit frequency, activity decay
Whether partner traffic quality is improving
Campaign cohort
Month campaign launched
Clicks, conversions, CPA, ROI
Which campaign vintages produce lasting results
Vertical cohort
Vertical of partner activity
Revenue mix, margin, compliance rate
How vertical concentration shifts over time
Reading a Cohort Retention Table
A cohort retention table shows each cohort as a row and each subsequent period as a column. The cell value represents the percentage of that cohort still active (or the revenue retained) at each interval. For example, if your January partner cohort shows 80% active in month 1, 55% in month 3, and 30% in month 6, you know that half your partners disengage within the first quarter. If your June cohort shows 80%, 70%, and 60% at the same intervals, your onboarding improvements are working.
Compare cohort curves, not single data points. A cohort that starts with a lower activation rate but retains better by month 6 is more valuable than one that spikes early and decays. The shape of the curve matters more than the starting point.
Running Your First Cohort Analysis
Define the cohort grouping: typically the month a partner was activated or a customer was referred
Select the metric to track: active rate, revenue, conversion rate, or traffic volume
Set the observation window: 1 month, 3 months, 6 months, 12 months after cohort entry
Build the retention or performance matrix: one row per cohort, one column per period
Overlay external events: did you change onboarding, commission rates, or campaign strategy between cohorts?
Compare cohort curves and identify the inflection points where behavior diverges
Common Cohort Analysis Mistakes
The most frequent mistake is using cohort analysis to confirm what you already believe. If you changed your onboarding process in March and the March cohort performs better, that is correlation -- not proof. Other confounding factors (seasonality, a single large partner, market conditions) can explain the difference. Always control for partner size distribution, vertical mix, and external events before attributing cohort improvements to a specific change.
Another common error is using cohorts that are too small. A cohort of 8 partners is not statistically meaningful. If your program recruits 15-20 partners per month, consider quarterly cohorts instead of monthly ones. The goal is patterns, not noise.