Currently, the way Google Analytics separates users on AMP and non-AMP pages can make it difficult to get a full picture of user behavior across the two page formats. To help make this analysis easier, Google is updating the way it counts and reports site visitors to AMP and non-AMP pages in Google Analytics by unifying user IDs when someone visits a domain via AMP and non-AMP pages.
Because the change unifies users across both page types, it will mean some reporting fluctuations. Here are the implications to note as this change takes effect over the next few weeks:
- User and session counts will go down over time as Google recognizes that two formerly distinct IDs are in fact the same user.
- When the change occurs, the metric New Users may rise temporarily as IDs are reset.
- Metrics like time on site, pageviews per session and bounce rate will rise consistent with sessions, with AMP and non-AMP pageviews no longer being treated as multiple sessions. This will continue until all users who have viewed AMP pages in the past are unified. Google says this can take a short or long period of time, depending on how quickly users return to a site or app.
The update does not affect AMP pages served from the Google AMP Cache or any other AMP cache or platform experience at this point. Google is focusing first on fixing the issue for user visits to publisher domains first.