Understand reports on placements
When you run reports on placements, it's important to keep these key concepts in mind:
The same ad unit can be in more than one placement.
Placements can overlap, therefore total values for a group of placements could be higher than the total values for the ad units they contain.For example, Placement A contains Ad Unit 1 and Ad Unit 2. Placement B contains Ad Unit 2 and Ad Unit 3. A report on Placement A and Placement B includes data for Ad Unit 2 twice, because it's found in each placement.
Updates to the ad units in a placement are reflected only from the time of change.
Previous reporting data for the placement isn't updated. Reports on the "Placement" dimension show historical data for each placement, based on the ad units that were in the placement as impressions and clicks were recorded.For example, Placement A contains Ad Unit 1 and Ad Unit 2. On June 15, you add Ad Unit 3. A report on Placement A for the month of June shows data for Ad Unit 1 and Ad Unit 2 for the whole month, but only shows data on Ad Unit 3 from June 15 forward.
- Reporting on Placements after the placement creation date
If you add the Placement dimension to a report, you can only report on data after the placement creation date.For example, let's say a placement wasn't created until 5/11 and you've selected the Placement dimension for your report. We can't report on that placement's data before 5/11, because it doesn't exist in the historical tables.However, if you add the Placement filter to a report without the Placement dimension, then you can report on data for all ad units that are currently connected to that placement, even for dates before that placement was created.For example, on 5/30, use placement as a filter to obtain past-month delivery data on ad units associated with that placement as of 5/30. The output will include data for the entire month, even though the placement was only created on 5/11.