Marketing / Lifecycle
Unsubscribe Rate unsub rate (distinct from spam-complaint/abuse rate)
The share of email recipients who opted out after a send.
The fork, why two teams get different numbers
DENOMINATOR fork: unsubscribes / DELIVERED vs / SENT vs / OPENED (a much smaller base that produces a scarier-looking rate).
In the Metric Library
- The full fork, both definitions worked all the way through
- The trap that makes the number lie, on a real export
- Every formula variant, spelled out
- The reconciliation anchor, what to tie it to and when to refuse
Reference: M3AAWG sender best practices (reference) · CAN-SPAM Act opt-out requirement (reference)