It’s Time to Break Up With the Pie Chart
Pie charts rely on our audience to decode quantitative information by comparing angles and area, which is actually quite difficult to do
My old high school recently sent out their alumni magazine which featured the VCE (Victorian Certificate of Education) results of the Class of 2018. The report was lovely and well designed, but one thing, in particular, caught my eye. They used a donut chart to display the university courses that the students were accepted into.
The chart looked a little something like this…
I have changed the data slightly to deidentify the school.
So, what’s wrong with that you ask? Five years ago, I probably would have told you, “nothing, it looks great”, but the more I study data visualisation the more I understand why pie/donut charts are just trouble.
Pie charts rely on our audience to decode the quantitative information by judging and comparing angles and area, which is actually quite difficult to do. Studies have shown us that it is far easier for us to compare length and position (bar and line chart), than area and angle (1,2).
With a donut chart (which is just a pie chart with a hole in the middle — stay with me, don’t get hungry)…
