Reporting discrepancies are common and expected when multiple systems are used to measure line item delivery. This can include differences between the user interface and reporting.
Also, when an ad server delivers line items that are hosted by a third party, or when comparing metrics between different platforms like Display & Video 360 and Campaign Manager 360, reporting discrepancies between the two systems will occur. It is common to see campaign variances of up to 20%.
Discrepancies may result from:
- Latency: Lag between an initial line item request and the appearance of the creative can lead to differences in counts. For instance:
- A user will often navigate away after the browser receives the Display & Video 360 line item request but before the third party responds with the requested creative.
- A user may click on a link but navigate elsewhere before the landing page has loaded.
- Network connection and server reliability: A third-party ad server may fail briefly or encounter an issue that prevents it from logging an impression.
- Ad blockers: Ad-blocking software can prevent the line item from being delivered by the third party after Display & Video 360 has already counted an impression.
- Low impression goals: A small numerical discrepancy can cause a high percentage discrepancy if the line item delivered few total impressions.
- For example, if you have a campaign delivering 100 impressions per day, a single-day discrepancy of 30 impressions will lead to a single-day discrepancy of 30% even though the actual number of missed impressions is low.
- Filtering: Ad servers have different methods and timing for filtering impressions from spammers, bots, spiders, back-to-back clicks, link analyzers, and other automated or non-representative web traffic.
- Different measurement providers and methodologies: Discrepancies can arise when different measurement providers have different methodologies for their measurement.
Between Display & Video 360 and Campaign Manager 360:
- Counting Methodologies:Display & Video 360 and Campaign Manager 360 count impressions at different points.
- Display & Video 360 counts an impression when it wins a bid and requests the ad.
- Campaign Manager 360 counts an impression when the ad creative begins to render (Begin to Render standard). These distinct events rarely align perfectly.
- Data Processing Times:Data processing and invalid traffic filtering differ. Generated reports in Display & Video 360 and Campaign Manager 360 reflect final numbers more accurately than real-time interface statistics in Display & Video 360, which may fluctuate for 48–72 hours.
- Spam filtering:Variations occur because each system applies invalid traffic filters at different times.
- Creative setup:Third-party trackers or tags can cause systems to count impressions at different points.
- Location reporting:
- Display & Video 360 uses the IP address from the bid request to determine location.
- Campaign Manager 360 determines location when the ad renders. These may differ if the user moves or network factors change.
- Attribution models: Attribution models define how conversions are counted and which impressions or clicks get credit for those conversions. Because the counting method is different, there will be discrepancies between different attribution models. When comparing two data sources (including the user interface vs. downloaded reports), ensure the attribution models are identical.
- Data sources: There can be discrepancies between YouTube reports and Standard reports because they use different data sources. Learn more about Report on YouTube & partners line items .
- Intended behavior: You shouldn't compare the performance data of the general report with the keyword or page category report. An impression reported in the general report can be attributed to more than one keyword, similarly to more than one page category. Impressions in both reports aren’t de-duplicated for keywords or categories.
Compare reporting data
When investigating potential discrepancies between systems, follow these best practices. This applies to Display & Video 360 and Campaign Manager 360, or with third-parties.
- User generated reports:Always compare data from generated reports. Statistics shown in the user interface (especially for the last 48-72 hours) are often preliminary and may not include full invalid traffic filtration.
- Match reporting periods:Ensure the date ranges are exactly the same in both reports.
- Align timezones:Verify that both reports are set to the same time zone.
- Consistent filters:Confirm that identical filters (for example, Advertiser, Campaign, Line Item, Placement) are applied in both systems' reports.
- Sufficient data volume:Comparisons are more reliable with a significant number of impressions (for example, over 1000). Small volumes can show large percentage differences from minor absolute variations.
By understanding these factors, you can interpret reporting data better and distinguish between expected variances and potential issues.
