Google has lost data in the Google Search Console’s search analytics and performance reports starting on Dec. 1 . Specifically, Google said image search data was lost because of a bug. It is not clear how much data was lost and over what period of time but we do know that when you filter your search analytics and performance reports by image search, on Dec. 1, it may be missing some reporting data.
What Google confirms. Google posted on the data anomalies page, “December 1 onward: Some data for clicks in Google Images from mobile devices was dropped. This change only affects Search Console reporting, not your actual performance on Google Search.”
John Mueller from Google confirmed that this was a bug and not an intentional change to how Google reports on image search.
Why it matters. When you are looking at your search analytics and performance reports in Google Search Console and you see a dip in traffic and impressions, it might be related to this bug. If you further filter on image search, you should be able to see the extent of the data issue.
Google did add, “This change only affects Search Console reporting, not your actual performance on Google Search.”
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