We typically lose less than 1%. It was 0.6% in March. As mentioned earlier, it's better to talk about %'s than absolute numbers. For example I think 100 euro is reasonable if you're making 20,000 per month.
Google are shooting themselves in the foot. I don't get this :
1. They claim 'invalid traffic', yet they are the one's who choose which ad's to display.
2. They are clearly displaying irrelevant ad's a lot more then before. Targeting is screwed up.
3. What constitutes 'invalid traffic'? A bounce back in 'x' seconds? A close of window? Nobody at Ad sense has actually told us what 'invalid traffic' technically means.
4. They adjust these figures at the end of the month. How? What are they looking at?
It it bewildering to comprehend the arrogance of Google in this situation. They expect us to run ads, which are chosen by Google, and then simply accept that a portion of the clicks actually were 'invalid traffic' without explanation or reason.
Screw that. I've removed adsense from a lot of my sites that used to make a small amount of $$ from it, i refuse to put up with this nonsense.
Makes you wonder if Google are still charging the advertisers. Any reports of Adword's customers getting reimbursed for 'invalid clicks'?
Google as a company just look more terrible and unethical with every month it seems.