It's been 15 days since I upgraded my web host from a VPS to a private server (within the same company). In the day after the upgrade my adsense CTR dropped by half and my CPC increased by about 70%. Nothing was changed on the website. What could have caused this CTR drop?
Was there at least an offset since your CPC went up by 70%? Or are you negative? Google uses sophisticated click fraud detection systems and web server IP is probably one factor.
I don't think that the server upgrade is the reason causing the CTR drop. If you are saying that your traffic drop, then it is possible. You gotta investigate what is the actual reason, I believe it is due to your major keyword which providing good CTR is dropping after server upgrade. However, it should be back to previous after some time
I also highly doubt that the issue is from your server change assuming that you havn't broken anything in the process. I have done several server changes, the last one less than a month ago, and have seen no issue, and can't think of any reason their should be an issue again assuming everything is the same on the new server as it was on the old.
I can think of 2 possibilites if you haven't changed your site content or hosting files. 1- Site speed might have been changed after moving to a different server. 2- The new server may have better or worse network connections than the old server. Therefore your site might not have been visible anymore in some parts of the World if the new server has worse network connections, or your site might have gained more visibility in the World if the new server has better network connections.
It's your site speed.. Already tried and tested that some sites get more click when site is really slow.. I guess depend on the niche.. I had a site that was getting a high CTR with shared hosting, Transferred it to a VPS and speed was up but CTR was down. And Since November, my site slowed down again due to a plugin and CTR was up, it was good but problem was I can barely edit my post and site so had to remove the plugin and clean DB, site speed was up again but CTR went down.. It only happen to 1 site so it really depends on a lot of things..