Much has been said in pro and against the use of pie charts… And the discussion is by no means something new For example in 1923, the American economist Karl G. Karsten warned us against the pie chart. Karsten’s claims in his book Charts and Graphs are remarkably similar to those heard today:
The disadvantages of the pie chart are many. It is worthless for study and research purposes. In the first place the human eye cannot easily compare as to length the various arcs about the circle, lying as they do in different directions. In the second place, the human eye is not naturally skilled in comparing angles… In the third place, the human eye is not an expert judge of comparative sizes or areas, especially those as irregular as the segments of parts of the circle. There is no way by which the parts of this round unit can be compared so accurately and quickly as the parts of a straight line or bar.
If you are interested to read more about the history of the controversial use of the pie chart, take a look at this post by Dan Kopf.
