Formula
(Starting MRR - Contraction - Churn) / Starting MRR x 100
How to measure
Track a fixed cohort's starting MRR, subtract churn and downgrades over the period, and divide by the original starting MRR, capping the result at 100%.
Why track it
GRR isolates retention quality from expansion, revealing churn problems that a high NRR built on upsells could otherwise hide.
Example
The same $500,000 cohort loses $30,000 to churn and downgrades, giving a 94% GRR regardless of any expansion revenue.