Hi i have a CTR of about 1% (can't be exact google doesn't like) I have been told several times by people on this forum that this is quite low. I do however have quite a high number of page views per visitor. Would this account for the low CTR as adsense shows average clicks per page viewed? I would say about 3% of unique visitors click on an ad this sounds more acceptable to me.
CTR depends on few things: your niche - certain niche has low CTR (proxy sites for example), ad position, blending ads, where your visitors are from, etc. it is hard to say why its low without looking at your site
What's your niche? I own a few video sites and I'm lucky to see 1% but my article site gets closer to 22% ctr.
The most common reason for low CTR is that the Adsense ads being displayed are not relevant to the interests of the people who are visiting your site. It's also possible that your ads are not positioned in such a way that it is easy for your visitors to see them and click them. Furthermore, certain types of sites don't do well: forums, general blogs, technical sites, sites about making money with Adsense, or sites that are so specialized that Google has few if any ads that relate.