One of my sites has gotten a typical amount of traffic the past two days, enough traffic to typically generate 5-15 clicks per day, yet there have been zero clicks from there in two days. I realize that CTR will fluctuate, but I think that this is extreme. Things have been normal on my other sites.
wow happened to two of my sites also. I did some editing and made the site look 100x better and clicks are gone, but because for some reason now im getting PSAs! its weird i was doin some testin with the URL (since I had this problem 2 months ago) and i can get ads on www.myurl.com/index.php/ but not on www.myurl.com/index.php! the backslash makes a difference for some reason and with the backslash my pictures dont show up. Really puzzling!
With few visitors it is very likely to fluctuate this wildly. Just build content and quality links. More visitors > more money and more predictability (though there are still fluctuations)