---
slug: kohorten-und-amortisation
title: "When has a new customer paid for themselves?"
category: berichte
locale: en
updated: 2026-10-16
keywords: ["cohort","payback","repeat purchase","retention","contribution margin","new-customer cost","lifetime value"]
questions: ["How do I read the cohorts under “Commerce & products” for repeat purchases, margin per customer and payback?","Cohort analysis","Payback period of new customers","When does a customer pay back","Customer lifetime value by month","Repeat purchase rate by month","Shop retention","CAC payback","Why do the cohorts start before measurement began?","Which orders are behind a cohort cell?","Who bought again in the third month?"]
url: https://bench.metrunio.com/en/help/kohorten-und-amortisation
---

# When has a new customer paid for themselves?

**How do I read the cohorts under “Commerce & products” for repeat purchases, margin per customer and payback?**

Under “Commerce & products”, the customer cohorts group customers by the month of their first measured purchase. For each following month they show how many bought again and how much contribution margin per customer has accumulated; “Paid back” names the first month in which that amount reached the new-customer cost of the first-purchase month.

New-customer cost on its own does not tell you whether it is too high. 40 euros for a customer who orders once for 30 euros is a loss; the same 40 euros for one who comes back every month can be earned back within a few months, depending on what each order leaves after costs. The cohort view shows which of the two is your case.

## How it is calculated

| Column | Meaning | Kind of number |
| --- | --- | --- |
| First-purchase month | The month of the first purchase Metrunio measured from this customer, in your account’s time zone | measured |
| Customers | Identifiers whose first purchase fell in this month | measured |
| New-customer cost | Ad spend of the month divided by the attributed new-customer orders, the same calculation as the metric above | attributed |
| Month 0, 1, 2 … | “Contribution margin per customer” view: margin per customer, summed up to the end of that month. “Repeat purchase” view: the cohort size in month 0, then the share of customers with at least one purchase in that month | measured |
| Paid back | The first month in which the accumulated margin per customer reaches the new-customer cost | calculated from both |
| Coverage | Share of orders whose contribution margin could be calculated | measured |

An asterisk marks the current month: it is not over yet and its value is still growing. A dagger on the first-purchase month means it falls within the first 90 days of your measurement. Someone who shows up there as a new customer may well have bought from you before, just not measured.

The cohorts start with the oldest order Metrunio knows, including order history loaded later. They can therefore lie before the measurement start the overview shows, which only counts from the first contact measured as it happened. For the months before that there are orders, but no measured ad contacts.

## The orders behind a cell

Click a cell to see the orders it counts: the purchases in that month by customers of this first-purchase month, with time, order number, value, contribution margin and whether it was the first or a repeat purchase. Each order leads to its journey, that is, the contacts before it. The total and the number of customers at the top are those of the cell; a selected website applies here too.

## Why “Paid back” stays empty

- **No costs:** no ad spend is imported for the month. Without costs there is nothing to pay back.
- **No new customers:** no new-customer order of the month is attributed to a campaign, so the cost cannot be spread over anyone.
- **No margin:** the orders carry no net value or cost of goods.
- **Not yet:** everything is there, the amount simply has not reached the cost so far.

## Limits you should know

- A repeat purchase only counts if it finds its way to the same identifier: through the customer account (`userId`) or the same browser. Someone ordering without an account on another device appears as a new customer in a later month. The view therefore states how many customers carry a customer account and how many your shop itself reported as new.
- New-customer cost belongs to the first-purchase month, not to the individual customer. A cohort formed in the month of an expensive campaign carries its cost, even if some customers came without advertising.
- An order without net value or cost of goods adds nothing to the margin, but the division is still by all customers of the cohort. The figure then errs on the low side; coverage tells you what share of orders it rests on. Revenue never stands in for margin.
- You can load older orders through `/v1/server/backfill` up to two years back. Only then do early months have their history. However, they are only kept as long as the retention period in *Settings* allows (180 days by default, 90 on the Start plan). Raise it before loading; anything older than the period is deleted by the nightly maintenance, and your cohorts start later.
- Subscription renewals count as repeat purchases of their cohort, provided you mark them as such. If a customer’s first measured purchase is already a renewal, their subscription started before measurement: they are in no cohort, rather than showing up as a new customer of a month in which they only kept paying.

## Also asked

- Cohort analysis
- Payback period of new customers
- When does a customer pay back
- Customer lifetime value by month
- Repeat purchase rate by month
- Shop retention
- CAC payback
- Why do the cohorts start before measurement began?
- Which orders are behind a cohort cell?
- Who bought again in the third month?

## Related

- https://bench.metrunio.com/en/help/neukundenkosten-und-deckungsbeitrag
- https://bench.metrunio.com/en/help/aufbewahrung
- https://bench.metrunio.com/en/help/shop-bestelldaten-senden
- https://bench.metrunio.com/en/help/werbekosten-importieren
- https://bench.metrunio.com/en/help/welche-kennungen
- https://bench.metrunio.com/en/help/abo-folgezahlungen