# V2 Retention Cohort Analysis

`@v2/retention-cohort-analysis` builds the Phase 72.5.2.4 retention cohort
surface for day-1, day-7, and day-30 retention curves segmented by acquisition
source.

The package composes `@iris/analytics-cohort` for daily cohort construction,
retention point calculation, adjacent cohort comparisons, and report output. It
applies the `v2-retention-cohort-analysis-v1` policy and exposes aggregate
retention rates without raw account IDs.

Targeted verification:

```bash
pnpm --filter @v2/retention-cohort-analysis run typecheck
pnpm --filter @v2/retention-cohort-analysis run test
python V2/ue/Tools/check-v2-retention-cohort-analysis.py
```