# Observed Cohort Value and Retention Experiment ## Cohort basis The unit is one acquired customer over the supplied year. There are 100 acquired customers; no active-customer count or later-year retention history is supplied. This supports observed contribution value rather than an unlimited lifetime estimate. ## Contribution and acquisition bridge Revenue per acquired customer is GBP 20,000/100 = GBP 200. Gross contribution is GBP 10,000. Subtracting GBP 1,000 servicing leaves GBP 9,000, or GBP 90 per customer before acquisition. CAC is GBP 4,000/100 = GBP 40. Observed contribution/CAC is 2.25; after acquisition the cohort contribution is GBP 5,000. ## Interpretation Do not label GBP 200 as profit LTV. GBP 90 is the observed one-year contribution measure. Acquisition payback timing cannot be calculated because purchase dates and cash timing are absent. Future retention remains unknown. ## Experiment and handoff Proposed design: randomly allocate consenting eligible customers to a useful reminder or holdout. Retention lead should record repeat-purchase rate and incremental contribution over a pre-agreed window, including reminder costs and opt-outs. Stop messages to anyone withdrawing consent. Confirm sample size before treating a difference as reliable. ## Scope and verification Provide planning estimates, not a valuation or investment recommendation. Historical cohort averages do not establish an individual's future behaviour. This is a worked synthetic example using the user-supplied material. Source authenticity, implementation and real-world outcomes have not been verified; proposed follow-up actions are not completed checks.