Note: This topic applies to reports created using Reports in the Index UI and the Reporting API.
Metrics like ad spend and impressions can show inaccurate totals when summed. This is because a single event, for example an impression, can be associated with multiple dimension values, for example multiple Privacy Sandbox topics. As a result, if you perform any summing to your reports, you may see incorrect totals.
We recommend that you avoid performing any additional summing on your end to the metrics in our reports.
An example: A publisher has two Privacy Sandbox topics defined
An article on a publisher's site titled "Predictions for the Superbowl" has the following topic tags:
Sports
- News
Any impression that is associated with that article can show up in reporting, in the topic_name field, with multiple associated topic tags, for example:
| Date | Topic Name | Impressions |
|---|---|---|
2/14/2024 | Sports | 500 |
2/14/2024 | News | 500 |
If the Media Owner sums their report, they'll see 1,000 impressions instead of 500, which is the true number.
