If you can narrow down which site(s) are giving the low paying clicks, you might be able to block them with the Competitive Ad Filter in Adsense. Hope things get better for you
Any PSA clicks as well as any invalid clicks will be included in the click totals, but will obviously not have any earnings associated with those clicks, which could be why you are seeing $0 earnings.
LOL, I have to say that I double checked directly with one of the AdSense team members one minute before posting that information, so I would say I'm pretty accurate
Jenstar: The site doesn't get any site targetted ads for now. I thought of that but nope. I don't get PSA-s either jdi_knght: I will certainly work on that but seems like without a good script it won't be easy. Thanks Jarodboy: I don't know if I get 0c clicks but I surely get lots of 1c ones ...
People in other geolocations could be seeing PSAs, even if you aren't. Set up an alternate ad, then you will know for certain if it is a PSA issue.
GA sucks, sometimes i got 55 clicks with almost $2 !?!?! But my friend with YPN is getting ~$1/click :/