Let me explain why you should avoid pie charts — and donut charts — in most documents and presentations.
Pie charts are easy to create and they’re colourful and you might want to include lots of them in the reports and slidedecks you write.
But there are lots of problems with them:
- they are difficult to interpret when there are lots of slices in the pie
- especially if some of the slices are very thin
- adding data labels makes them more cluttered and using a table for the data would be clearer
- putting pie charts side by side does not show trends.
In most cases I think you would be better off with a column or bar chart, or a table.
I think there is an exception to this. Pie charts with only two slices, where both are fairly large, are easy to interpret since you’re just showing the relative size difference of two variables.