What is a cohort?
Cohort is a group of clients who share a characteristic or event in a certain period, such as the month they join the agency. The analysis follows the evolution of these groups over time, allowing similar experiences to be compared without treating the entire portfolio as if it had started at the same time.
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Why group customers by entry?
An agency's portfolio can mix new and old contracts, different services and different market moments. An overall retention average can hide difficulties concentrated in customers from a specific class. By separating the groups, the manager is able to investigate changes in sales, onboarding and delivery.
The chosen group must answer a practical question. An analysis by start month can help look at the first few months of the relationship. A breakdown by service may indicate processes that warrant review. Identify the input event and keep this rule stable.
How can you calculate cohort retention?
Imagine ten customers who started their contract in January. If seven remain active at the end of the third month of tracking, retention at that point is seven divided by ten, or 70%. The original group remains the denominator; new customers who joined later are not added to it.
The agency needs to define how to handle cancellations and reactivations and what date marks the entry. Compare equivalent months of contract life, as a recent group has not yet completed the same observation period as an older one. Also record the size of each group.
What errors harm the comparison?
A very small group can vary greatly with the departure of a single customer. Mixing annual contract clients and short-term projects, without explaining the difference, can also produce misleading conclusions. The indicator shows an observed pattern, but does not alone identify the cause of a cancellation.
Avoid comparing the third month of one class with the twelfth month of another as if they were equivalent experiences. Also investigate price adjustments, service changes, and record quality before attributing a fluctuation to a specific person or campaign.
Where does Zenit OS support this tracking?
Operation navigation includes Retention & Cohort for those who have access, and the product offers customer monitoring. Confirm with the team which filters and criteria meet your process; the illustrative calculation on this page does not claim that the system uses exactly the same definition.
Access to the operation depends on plan, role and configuration. To discuss an analysis applicable to your portfolio, schedule a demonstration with the entry periods and cancellation criteria that the agency already uses.
Frequently asked questions
Does a cohort need to be monthly?
No: the interval can be weekly, quarterly or other, as long as it is appropriate to the volume and management question.
Do new customers join old classes?
Once defined by the entry month, each customer belongs to the group corresponding to its own beginning.
Does the retention show why there was a cancellation?
It indicates how many remained according to a rule; the reasons require additional records and investigation.
Does a small class provide statistical certainty?
Few contracts make the percentage sensitive to individual changes, so interpretation needs care.
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