Google Analytics Referral Spam
On March 17th, 2015, Google Analytics showed that my site got a big spike in referral traffic from a web site that didn't make sense as a legitimate referral site. I went to a domain name registration look-up site Whois.net and found that the domain had been registered the day before. More investigation showed that this was "referral spam" where no one ever looked at my site. The spammer spoofed the Google Analytics ID in a call to Google Analytics, so it showed up as a referral. In 2014, 2015 on up to about 2017, this was common, but Google Analytics has gotten much better at removing referral spam before you get to reports, so I've stopped reporting on it and have removed the various specific articles from my tech blog.
Trends in Referral Spam
It is hard to tell just how often this is occurring on any site other than one’s own, but Google Trends may offer some additional information, as shown in the dynamic figure below showing interest in the search term “referral spam”. Use the link https://trends.google.com/trends/explore?date=all&geo=US&q=referral%20spam. Unfortunately, you can't embed Google Trends data anymore.
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