Draft reference — content review pending
Customer Churn Rate
The percentage of an eligible starting customer base that no longer meets the agreed active, contract, or purchase definition during the period.
Business question
What share of the eligible starting customer base was lost under the chosen churn definition?
Formula
Customer churn rate = (customers lost from the eligible starting base ÷ eligible customers at period start) × 100.
Calculation notes
Define the eligible starting base and the event that counts as churn. Keep new customers outside the starting-base denominator.
Edge-case guidance
If the starting base is zero, report the measure as not available. Explain how paused, seasonal, merged, or contract-ended customers are handled.
Required data
| Input | Type | Status | Available source hints |
|---|---|---|---|
| Lost starting customersEligible starting customers meeting the selected churn definition. | Number | Required | CRM · Excel · Google Sheets |
| Starting eligible customersEligible customer base at the start of the period. | Number | Required | CRM · Excel · Google Sheets |
Interpretation
Use churn to identify loss in the starting base and investigate reasons, segments, and timing rather than reading the percentage alone.
Caution
Churn is definition-sensitive and may be affected by seasonality, contract timing, inactivity windows, and customer data quality.
Implementation recommendation
Pair the rate with reason codes and a retention view; do not optimize the percentage without understanding which customers are leaving.
Target guidance
Set the first target from a comparable historical baseline for customer churn rate, then adjust it for strategy, capacity, seasonality, data quality, and relevant market or regulatory context. Review the direction with the accountable business owner rather than treating any external benchmark as universal.