Cohort Analysis for User Groups

Cohort analysis is used to group users based on a shared characteristic, usually their signup date, and then track how those groups behave over time. Instead of analyzing all users together, cohort analysis helps identify patterns such as whether users who joined in a specific month are more engaged or more likely to return.

A cohort is typically defined by the period in which users first joined the product. For example, all users who signed up in January form one cohort, while users who signed up in February form another. Analysts then track how each cohort behaves in terms of sessions, events, or purchases.

Cohort analysis is especially useful for understanding retention, engagement trends, and product performance over time. It helps answer questions such as whether newer users are more active than older users or whether product changes have improved retention.

For beginners, the goal is to:

• Understand what a cohort is
• Group users based on a common time period
• Track behavior across different cohorts
• Compare engagement between user groups

• How many users signed up in each period
• How different cohorts behave over time
• Whether engagement improves or declines
• Differences between user groups

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The Basic Pattern

SELECT column_name
FROM table_name;
  

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Examples

Example 1 — Group Users by Signup Month

Example 2 — Count Sessions by Signup Cohort

Example 3 — Find First Activity Date per User

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Practice Tasks (Your Turn!)

Task 1

Count the number of users by country.

Task 2

Find the total number of sessions for each traffic source.

Task 3

Count the number of orders by order status.