Tips for visualising data like The Economist

Economist Education: The Economist’s journalists prize simplicity and often use basic charts to visualise data. But they use fancier ones too: which types, and why?

Elizabeth Lees: Bubble charts are one example. There are disadvantages to them: for instance, the human eye can’t accurately compare the size of the circles. However, bubble charts are visually engaging and good for displaying huge ranges in data. You can also use labels to show the exact values of data points. This same information could have been presented in a table, but this is more interesting and the steel data point jumps out immediately:

Thermometer charts are another type of visualisation. They work well when you want to compare two categories, such as men and women or the same data point across two different years. This saves space and makes it easy to see the difference between categories:

Economist Education: How do you go about choosing the colour palettes of charts?

Elizabeth Lees: We typically keep to a limited colour palette. This makes it easy for readers to identify your work and keeps a cohesive style across your charts. It also removes the need to make colour decisions every time you make a chart, saving time. At The Economist we have consistently used one main colour—dark blue—and another, secondary colour—light blue. These have a high contrast so you can see the difference between them easily. 

Our purposely limited palette lets us use up to six colours very quickly. Beyond six, your reader might struggle to see the differences between your data points. If you do have a lot of series that you want to show, consider using colour to emphasise your main indicator:

Most of the time, using colours extensively is unnecessary and can detract from the story you’re trying to tell in the chart. But an exception, when we might stray from our colour palette, is for well-known political parties, which a lot of people associate with a certain colour:

You can use colour to highlight your data, whether through bolding text, using a tint or using one strong colour to highlight the key message of your data. This can be very effective and eye-catching. 

In the course video The Economist’s data journalists go on to discuss the characteristics of bad charts and provide practical hints on how not to make your visualisations too complex. Our full course covers these subjects and many more: for further information download the prospectus here.