When navigating the new GA4 interface to analyze data, especially when you are using the new Explore section to create custom reports, you are likely to come across a new type of alert called a data threshold.
This alert is in addition to sampling, which will still occur (similar to how it works in the current version of Google Analytics). So, when analyzing data, you’ll have to keep an eye out for both sampling and data threshold alerts.
This is critical, because if you accidentally report on data when a data threshold is applied, you aren’t reporting on the whole data set. Therefore, your insights and takeaways may not be accurate.
Data thresholds withhold data from a report to prevent you from identifying who the users are within your data set. Google specifically states that their intent is to prevent you from “inferring the identity of individual users based on demographics, interests, or other signals present in the data.”
Google applies data thresholds when you analyze data based on a small number of users, especially when your analysis contains user-identifying information like demographic data, custom dimensions, and some user-generated fields like user ID.
Unfortunately, there isn’t currently any clarity on what the exact thresholds are (like user count volumes) that will trigger Google’s data thresholds.
Google will provide an alert in the reporting interface when a data threshold is applied.
This is an example of an alert within the Explore section of GA4:
This is a zoomed in view of the same alert within the Explore section of GA4:
This is what you will see when you click on the alert and open the information box:
No, data thresholds are set by Google and can’t be changed.
If a data threshold is applied, the best course of action is to revisit your report analysis and either expand the volume of users within the data set (such as by selecting a larger date range) or assessing the removal of user identifying information (like demographic data) depending on your analysis needs.
Hopefully this will help save you some time and headaches when reporting on data within GA4. If you need assistance with your GA4 property, please reach out to firstname.lastname@example.org!