Does Adsense cheat?

Hey guys, almost every month I can see a huge decrease of my page ctr and a low of my cpc independent of the ad fill rate (always 98-100%) and impressions.

I get around 10k page views a day so it should not change that much.

Most of the time this happens at the beginning of a new month and takes about 1 week to go back to the normal ctr/cpc.

On september 2 I changed my web-design. Please notice that the drop was already before the update.

Does anybody else experience this too? What are your thoughts on this and why do you think it happens?
Screenshots:


https://imgur.com/otMlDIa

We can't see the images as we'd need to sign up onto your home page to do so.

AestheticHustler said:

We can't see the images as we'd need to sign up onto your home page to do so.

Click to expand...

What do you mean, I haven't added anything from my home page

Edit: Should work now(imgur)
Before I added the screenshots from slack and it seems like that doesn't work