Chapter 39. How to Make Donut Charts
When used properly, donut charts can be an effective way to communicate comparisons in a unique way. When used improperly, they are the butt of jokes mentioned in the same vein as pie charts. In fact, donut charts are essentially pie charts with a circle in the middle, and in Chapter 93, I explain why you shouldn’t use pie charts. The big reason charts like bar charts work better than pie charts is that the viewer is comparing the length of the bars; not comparing the area of the wedges of the pie—and our brains are much better at comparing length than area.
So what’s the difference with donut charts?
One of my recommendations for practitioners that cannot quite let go of pie charts is to use five slices or fewer. Personally, I would not use more than two. When used for the specific purpose of showing a metric’s progress to goal, with one “slice” being the current state of the KPI and one “slice” being the remainder to goal, I think a donut chart works well.
I admit, a bullet graph would be the most efficient way to communicate the progress to goal scenario. A bullet graph would be processed faster by end users than a donut chart and also take up less real estate on a dashboard. It also works better for showing progress above goal because a donut chart stops once you get to 100%. If you think a bullet graph may be a more appropriate choice for your data visualization, see Chapter 26.
That being said, I don’t mind the extra real estate that ...
Get Practical Tableau now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.