|MOS was 71331|
How do I read a pie chart displayed as concentric circular rings of apparently uniform width? I have never seen such a pie chart in a book or an article, yet most of the pie charts shown in the "Pie Chart" help page are of this type.
The only pie charts I've seen in published documents have circles divided into wedges radiating out from the center. The wider the central angle of the wedge, the greater the percentage for that wedge's component of the whole pie. Their interpretation is so obvious I can't recall ever having seen them explained.
Would someone please explain how to interpret pie charts of concentric circular rings or tell me where I can find a published document using such charts?