Here's a screen shot from Google Analytics. It's my last months traffic, and this is the 'Frequency & Recency' tab.
So I believe that if I add up all the numbers under 'visits' I get 11,432, which is right, and if I add up all the numbers under 'pageviews' I get 14,785 and that's right as well. But, let's take the last line - the last line appears to say that 71 people, visited more than 51 times each, and they viewed a total of 243 pages between them - that doesn't seam to make any sense - did they view 9% of a page each time?
So that's clearly wrong - what's the error in my calculation?