Google said there was a bug of some sort that resulted in Google Search Console dropping data. The lost data is image search click data and you may see a drop in clicks between the dates of November 14th and November 19th. This has no impact on your rankings and traffic from Google search but rather this was a data bug.
What Google said. “Some image click data was dropped; as a result, you might see a dip in both click rate and CTR during this period. The issue has been fixed. This issue affected only Search Console reporting, not your performance on Google Search,” Google said.
When did this happen? Google said bug affected data between Thursday, November 14th and Tuesday, November 19th.
The impact. Again, this did not impact actual traffic to your web site. What was impacted were the performance reports in Google Search Console. So if you are looking at your data and you see a dip in clicks between November 14th and 19th, this may be why. You can further filter just image traffic in the performance reports as well.
Why do we care. SEOs, marketers and site owners may be looking at these Search Console reports and worry. This data anomaly has been documented and it impacts many users. Again, real traffic from Google search was not impacted by this bug, it is just a reporting bug.