Google has announced a change to how image impressions are counted in Search Console, effective April 6.
According to the company, the algorithm for counting image impressions has been adjusted, and adjustment that could lead to a drop in numbers.
Search Console improved the algorithm for counting image impressions in Search results. As a result, you may see a small drop in your image impressions in Search. This is not a drop in actual impressions, just a more accurate calculation of image impressions when type=image is specified in the Search Performance report.
As Google highlights, this doesn’t mean the actual impressions are down, just how they’re being counted. This will also not impact rankings in any way.
The notice should offer some peace of mind to webmasters wondering why their numbers were dropping after April 6.