In a quiet move, Google has posted that is removing query data from the Google Search Console report chart total s that identify as “anonymous queries” when a users applies a query filter to the report. This basically means that reported clicks and impressions could drop when you apply a filter. According to google, “an anonymous query is a query submitted [by] only a few users.”
The number of queries that are removed from the report totals will depend on the site, the company saying that “some sites will have very few unique queries; other sites will have a large proportion of anonymous queries.”
Google wrote on the page:
Chart totals no longer include anonymous* (rare) queries when you apply a query filter. Previously, the chart totals included all anonymous queries when a “Queries not containing:” filter was applied. Because of this, you might see a drop in clicks and impressions when adding a filter that excludes specific queries. We believe that omitting anonymous queries from all query-filtered results is more consistent.
It is explained in a help document why Google is removing these types of queries from reporting. “To protect user privacy, Search Analytics doesn’t show all data. For example, we might not track some queries that are made a very small number of times or those that contain personal or sensitive information.”
Back in 2011, when Google removed query data from reports when Google moved search results to HTTPS, it was about protecting user’s privacy to disallow people from sniffing Google’s searches. Now, with this change, Google is also removing some query data from totals in Google Search Console as well.