Earlier this month, we reported an outcry by a large number of SEOs who noticed Google Analytics show not set as the top referrer in the Search Engine Optimization report. Google told us last night, this was not a bug but by design.
John Mueller of Google did a hangout last night and I was able to ask him at the 5:55 mark into the video about it. He said that the Search Analytics report in the Google Search Console differs from the SEO report in Google Analytics because Search Analytics doesn't show many of the queries, and Analytics lumps those into a [not set] report.
Here is how John described it:
In Search Analytics if you look at the numbers of the queries that you see there, you will sometimes see that we show a top aggregated, maybe a hundred queries, and in a table below if you add the numbers together, you might see 70 queries or something like that.And the difference there is essentially queries that we filter out, and in Search Console we don’t show them separately and in Google Analytics they chose to call them Not Set.
So that is what you are seeing there, not something completely different, its not showing the difference that you’d have to calculate yourself.
I am not sure why it took Google so long to get me this answer and I am not sure if it changed - [not set] was not in the report a while back. So this is just unusual to me.
Here is the video embed at the start time:
Forum discussion at Google+.