Bubble grid charts: an alternative to stacked bar/column charts with lots of data series?

Stacked column charts with a large number of categories and data series can quickly become unclear. Deciphering this stacked column chart from the Home Office "Crime Outcomes in England andWales 2014/15 " for example, takes some work - in part because of some unfortunate design choices. 

(Click on the charts for a closer view) 

But even if the design was improved, by flipping the chart through 90° and applying some other formatting tricks, it would still be difficult for readers to see the main points at a glance.

So what to do ?

Small multiples - when stack bars just won't cut it . . .

Stacked bar charts can help readers make quick comparisons across categories. They can be particularly useful for breaking down responses to straightforward survey data - such as perceptions of services running on a scale from satisfied to dissatisfied - by demographic factors such as sex and age bands.

Formatting techniques, such as using white space to chunk related categories together, using axis labels to report category names and base sizes together, and thoughtful colour choices reflecting the logic of what's being charted, can all help make interpretation of stack bar charts fairly straightforward.  I've demo'd one approach to stacked bar chart design, showing how to use these and other formatting techniques in Excel 2016 to make charts to help non-technical readers out - not freak them out.

But sometimes, a stacked bar chart just won't cut it . . .