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📄 We recommend reading our Google Consent Mode (GCM) tech doc and using our GCM Support Knowledge Base when setting up Google Consent Mode.
Why does this GA4 drop in data happen? What can be done to reverse it?
Reasons why you may be seeing less data in GA4
Your Google Consent Mode implementation may have been done incorrectly.
Suggestion: Check your GCM implementation, for example, using Google’s Tag Assistant. We also outline some other methods on our GCM Support Knowledge Base.
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When using Advanced Google Consent Mode (GCM)(“advanced implementation” in the screenshot below from Google’s documentation), the drop in data in GA4 can also be related to non-consenting end users. So the previous improvement suggestion about CMP optimization is applicable here, too.
If you fulfill Google’s prerequisites for behavioral modeling with to Google Consent Mode (see screenshot below), you should also see improvement with that over time.
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How to reverse the GA4 drop in data with Advanced Google Consent Mode
Meet as many of the prerequisites listed above as possible. For example, driving more traffic to your website(s) can help to meet the thresholds that are required for behavioral modeling.
Use the data you do have from consenting end users to estimate overall numbers, either long-term — if you cannot meet the above prerequisites from Google — or until behavioral modeling from GCM kicks in for you.
Wrapping up
Depending on legal requirements and requirements from Google that you may need to meet, using a Google-certified CMP like Usercentrics CMP is most likely your best bet. Our CMP comes with Google Consent Mode v2 integrated, so we’ve got you covered!
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