swa66 - 9:54 pm on Apr 23, 2013 (gmt 0)
You lost CTR. And did not change page layout or anything like that...
Sounds like you benefited from the ugly arrows or something like that G might have stopped ?
Or you lost an image ad that got replaced by almost equally paying text ads - but aren't attracting as much clicks?
Now the ToS prohibits disclosing CTR. But the number you mention feels rather low - it depends on the content etc. (e.g. forums perform notoriously bad). I'd look into placement, layout etc to make the ads stand out a bit more/give them a more prominent place.
Also keep an eye on how your site looks on iPads and iPhones ... their usage is on the rise globally, so that's probably true for you just as well.