A couple of weeks ago my hosting account was hacked and many of my sites were infected with malicious files. One of them was a site with Adsense on it.
All the infected files were cleared up pretty fast. I feared that if the site will be infected for a long time, its organic positions could drop. Fortunately, it didn't happen and the traffic volume didn't suffer except of course during that one day where my site was blocked because it was infected.
However, adsense impression amount is now considerably lower than before. The ads are showing and I'm not able to locate what's causing the problem. Interestingly enough the page RPM has gone up, so the earnings are not much lower than before but still lower.
I've heard about attacks on Adsense sites where the hackers replace some of the ads with theirs or something like that. But I can't seem to find any evidence of that.
Here's the Google Analytics graph - View image: All Traffic Google Analytics
The 2 huge drops were when the site was blocked and then a few days later I had a problem with the Analytics tracking code. Anyways, you can clearly see how the Adsense impression amount has been much lower lately than a few weeks ago.
Does anyone have any ideas?