One of my sites is a very consistent adsense site, day in and day out. Gets about 15,000 page loads a day, with about an 8-9% CTR over a long time. Suddenly, as of two days ago, the CTR dropped to just over 4%. Cut in half. My traffic is still excellent, and the CPC is the same as usual. I looked at the site and it seems the same types of ads are showing. I have lots of pages, all with ads, so it's not just one ad spot on one page that is affecting it, it has to be the whole site overall. So, what could possibly cause around 20,000 people over the last couple days to only be half as interested as clicking an ad?
Until you said the same ads are showing I was going to say it's down to advertisers not advertising e.g. gardening is seasonal as an example, hence my gardening site goes up and down as no one is looking for chili seeds in Winter. So now I'm stumped as to what to suggest. Good CTR by the way.
My earnings went down as well and I am a partner with Youtube, my earnings are down over 50% each day and has been like that. I dont know why it fluctuates like this, its annoying because this is sort of like my second job.