The one (rare) situation in which it makes sense to use a single stacked bar chart
Nick Desbarats
Independent instructor and best-selling author, data visualization and information dashboard design | LinkedIn Top Data Visualization Voice | Workshop info, email list, etc. at practicalreporting.com
I’ve recently seen a few comments on LinkedIn from people who don’t feel that it ever makes sense to use a stacked bar chart to show the breakdown of a single total, like this:
It’s true that, if the main message of the chart involves precisely comparing the parts of a total with one another, a regular bar chart would be a better choice:
It’s also true that, if the main message of the chart involves showing what fraction of the total each part represents, a pie chart would be a better choice:
(BTW, if you believe that pie charts are the devil’s chart type, read this .)
If other chart types are better choices in those situations, when would it possibly make sense to choose a stacked bar chart? TBH, it took me a while to realize that there’s another type of insight that one might need to communicate about the breakdown of a total, and for which a stacked bar chart would be the truly best choice, specifically, an insight that involves showing subtotal(s) of the values of several parts:
If you were to use a regular bar chart or pie chart to communicate this type of insight, it would force the reader to do math in their head, which is definitely something to avoid since it dramatically slows down interpretation and increases the effort required from the reader:
Note, however, that if the main message of your chart involves showing what fraction of the total several parts represent, a pie chart becomes a better choice than a stacked bar chart:
领英推荐
So, to sum up, when showing the breakdown of a single total…
Consider using a stacked bar chart when showing subtotal(s) of parts is more important than…
So, yes, there is a situation in which it makes sense to use a stacked bar chart; it’s just that that situation doesn’t occur all that often in practice.
These guidelines (and others) are summarized in this handy-dandy decision tree, which is one of eight such tools that are included in my Practical Charts course :
Having said all this, if you need to show the breakdowns of several totals (not just one total, as we’ve seen so far), stacked bars become the best choice considerably more often:
When, exactly, are multiple stacked bars the best choice? That would require a whole other article, or you could just take the course ??, speaking of which…
If you’re interested in attending my Practical Charts course (and/or my Practical Dashboards course), here’s a list of my upcoming open-registration workshops .
To be notified of articles like this in the future, consider subscribing to my email list (one to three emails per month to level up your data visualization and dashboard design chops).
consultant
7 个月Because of the absence of common baselines, it's not my preferred graphical approach but!....for developing dashboards, you could have one stacked bar chart to serve as: 1. the "dashboard color legend" of categories (4-6 max preferably) - GIF attached below 2. Like you said Nick: the subtotal(s) of the values of several parts and; 3. A cross filtering visual serving also as a slicer when the user click on one of the stack. So in summary a stacked bar chart could be a legend, a visual and a filter, so yea I buy it. You changed my mind about it when reading your book. ????!
Data Visualization
7 个月I can't remember where I've seen a recent example, but one excellent use of a single stacked bar chart is as the legend of a choropleth map, where in stead of equal-sized keys, the keys are in proportion to data.
Digital Communications Specialist @ The World Bank | Data Visualization, Information Design
7 个月I remembered this example, although it isn’t tecnically a stacked bar, but more like an annotated, single-column chart. https://graphics.wsj.com/oil-producers-break-even-prices/
Data Storytelling & Information Design Expert ?? Founder of Parabole Studio ??
7 个月I also encounter a lot of hatred for stacked bar charts for some reason! Love the details in this article. *Shameless plug* I wrote about it recently too: https://www.theplot.media/p/stacked-bars
Strategy & Analytics | Clarity | Collaboration | Growth
7 个月Love this. I'll add that the order is important here too and that it should be geared toward highlighting certain groupings, or else the reader is back to doing math in their head.