Ok, Iv been trying to make some money with adsense the last 7 months or so. Look at these horrible stats. So last night, I thought to myself maybe I should make another proxy. The site was up for about 30 minutes and I get 1 click that gives me more than I have combined from my previous 7 months. How the hell does that work?
Your earnings highly depend on the site language, visitor's language and on the price of the keyword, that is why your stats look like that. Probably a more expensive ad appeared on your second site than the ads on your first one.
Earnings per click are always different, it's not random, how is that a big mystery? You need to read up on Adsense, this is waaaaaay too basic.