Okay, so I have only been using adsense on one website which is getting about 1,000 unique visits a day and has been pulling me 40 dollars a day consistently for about 2 weeks. Well...yesterday I placed some adsense blocks on 3 of my other websites which get some traffic and my over earnings have dropped! Did this happen because I placed adsense on my other websites...does google pay out less when you have your adsense ID pulling from different domains?
The Ctr dropped and so did your earnings per click. Try taking the other ads off your sites and see what happens.
I going to wait a couple days so I can get a data set. I've always wondered if google tracked your adsense ID to see what domain name's are pulling the ID. In result, if you have ads on non pageranked domains...they would serve you lower paying ads across your network of adsense websites. This theroy makes sense, it would help moderate all the made for adsense websites.
very interesting theory. I've been beating my head against the wall wondering why the sudden and severe downward spiral.
a week after removing the ads from my new site, earnings were up 34% despite a drop in visitors and clicks. it's only a week but it makes me wonder about other non-preforming sites
$40 per 1000 uniques is abnormally high, so your sudden drop could be a sign of things to come... but some people do believe that overall adsense epc is based on what you do account-wide, not just per site. i don't believe that pr is relevant to advertiser conversions. you can prove that for yourself by looking at domains that get type-in traffic, some of which can be very targeted... since there is no content, there can't be many links to raise the pr, but some of 'em make really good money.