I have a blog that exists for several years and it has something around 150 visitors per day (not pageviews). It has AdSense for about 14 days and not a single click was issued up to now.
How normal is it? I know blogs are not the ideal place for AdSense and it surely does not help that it is in portuguese, but considering the amount of visitors, do you think it may be some technical problem?
I've had ad channels with CTRs as low as .2%... so I would need 500 visitors to get 1 click... I think my math is correct. That was an English page and not a blog, so no, I don't think it's that unusual.
If you have a blog the chances of your visitors being the same ones every day to check the latest postings are pretty good. They are looking for your latest post not some ad which was recently placed. Plus, it's not likely the ad is in an ideal spot on a blog. Top center or top left is best. Anything other than these spots will see sharp declines in CTR.