This month I realy surprised, because my Blogs traffic and earning both decrease , before this will be right. I dont understand google behaviour But Why?
You just have to keep working on your site...dont stop adding contents and backlinks...I realized that when I stopped working on one of my websites, my earnings dropped...I guess I cant' just relax and expect automatic income.
Your adsense earning drop because of our traffic drop, your blog traffic drop is because you are not doing a great job. So, cant see anything wrong with adsense / google
I've got same problem with you... I just don't give up and create another 'niche' blog. Don't think adsense is automatic money...