The Standard Reporting API returns aggregated MPO performance metrics across campaigns, sellers, and seller-campaigns. This page explains how to interpret each metric.
Displays
A display is one ad serving event: one banner shown to a user, regardless of the creative format or the number of seller products visible inside it.
- 1 ad rendering = 1 display
- The display count does not increase with the number of sellers or products shown inside the creative
Examples:
- Single-seller creative: one ad containing one seller product was shown → 1 display
- Multi-seller creative: one ad displayed 4 seller products → 1 display (all 4 products appeared within a single banner)
Impressions
In MPO seller reporting, an impression is a seller/product-level exposure rather than a banner-level serving event.
- One banner can generate multiple impressions if it shows multiple seller products
- Impression counts are therefore not always equal to display counts
A useful rule of thumb:
| Metric | Measures |
|---|
| Display | One banner shown |
| Impression | One seller/product shown inside a banner |
Clicks
A click is a user click attributed to MPO delivery for the relevant reporting scope. In seller-level MPO reporting, clicks are interpreted in a seller-aware way, because MPO reporting tracks performance at seller and seller-campaign level rather than only at whole-banner level.
Cost
Cost is the advertising spend recorded for the selected MPO reporting scope and time range. Its interpretation differs by setup:
- Multi-seller MPO — billing is click-based. Cost reflects click revenue: the sum of the clicked seller CPC multiplied by the number of attributed clicks.
- Single-seller MPO — billing is display-based. Cost reflects display revenue under eCPM billing.
Depending on the endpoint, cost can represent spend aggregated at campaign, seller, or seller-campaign level.
saleUnits
saleUnits is the number of products bought from a given seller. This metric is used instead of a generic orders count because MPO transactions can involve multiple sellers in a single purchase flow.
saleUnits reflects seller-level purchased product volume, not basket-level order count.
Revenue
Revenue is the attributed sales value associated with the selected reporting scope and attribution settings. Because MPO reporting can be seller-specific, revenue interpretation depends on the attribution logic and seller scope used for the query.
See MPO Attribution for details on how attribution settings affect this metric.
CR (Conversion Rate)
CR is the conversion rate for the selected reporting scope. Use it as an efficiency metric to understand how effectively MPO clicks convert into attributed sale activity for the reporting slice you selected.
CPO
CPO is the cost per order (or cost per outcome) returned by MPO standard reporting. Use it to understand how much spend is required to generate attributed sale activity.
COS
COS is the cost of sale ratio returned by MPO standard reporting. Use it to compare spend against attributed revenue for the selected reporting scope.
ROAS
ROAS is return on ad spend: the revenue generated relative to advertising spend. Use it as the primary efficiency metric when evaluating MPO revenue performance against spend.
Key distinction: displays vs. impressions
In MPO, displays and impressions are not interchangeable. Confusing them is a common source of reporting misinterpretation.
| Metric | Measures |
|---|
| Display | The ad serving event itself — one banner rendered |
| Impression | Seller/product exposure within that banner |
- 1 banner served = 1 display
- 4 seller products shown inside that banner = 4 impressions
This distinction matters when comparing seller visibility, delivery volume, and campaign exposure across MPO reporting surfaces. 
