Normally I tend to write in this board only when I have problems with my adsense account. And I usually get really good advice.
Today I want to write because, after an awful month of April, May seems to be an excellent month: if things go on like this, it's going to be the best month ever for me.
The positive effect could be caused by a lot of reasons but there are two things that seem quite important to me.
The first thing is that at the end of april I moved my website from a cheap hosting to my dedicated server: the difference in between the two servers is like night and day.
The second reason might be only a coincidence but I have a feeling it's not.For the last two years I've been religiously adding a new page of useful content every day, but from the 15th of april I was busy and didn't update the website. Could this 'lack of updating' have helped, somehow?
Apart from that, yes CTR is tanking, but at the same time the value of every click is increasing.
Google Adwords is all about giving value to clicks, so I can understand why Google wants to see less valid clicks that pay more.