Just lately my CTR has been around 0-5% even though my traffic has increased. Yet, on lower traffic days my CTR is sometimes up to 50%. I am only taking about around 30 uniques a day though.
deviantlnx
3:09 pm on Apr 12, 2006 (gmt 0)
Not all clicks get recorded.
I am not sure exactly how Google decides which clicks count, but not all of them do.
jomaxx
4:44 pm on Apr 12, 2006 (gmt 0)
All valid clicks get recorded. The problem is that your traffic level is so low that you'll have to aggregate it, for example by doing month-over-month comparisons, in order to see a clear statistical pattern.