My site was averaging $.06 a click and about 3% CTR now it is $.08 a click and 5% CTR! hehe I just started adsense a few days ago so I'm pretty excited
CTR can fluctuate by a lot if there number of hits is not huge. In that case, it is more accurate to look at the monthly CTR. 5% is pretty high, if it maintains at that rate you are pretty successful.