Taking small steps to bring out the message
Jan 06, 2020
Happy new year! Good luck and best wishes!
We'll start 2020 with something lighter. On a recent flight, I saw a chart in The Economist that shows the proportion of operating income derived from overseas markets by major grocery chains - the headline said that some of these chains are withdrawing from international markets.
The designer used one color for each grocery chain, and two shades within each color. The legend describes the shades as "total" and "of which: overseas". As with all stacked bar charts, it's a bit confusing where to find the data. The "total" is actually the entire bar, not just the darker shaded part. The darker shaded part is better labeled "home market" as shown below:
The designer's instinct to bring out the importance of international markets to each company's income is well placed. A second small edit helps: plot the international income amounts first, so they line up with the vertical zero axis. Like this:
This is essentially the same chart. The order of international and home market is reversed. I also reversed the shading, so that the international share of income is displayed darker. This shading draws the readers' attention to the key message of the chart.
A stacked bar chart of the absolute dollar amounts is not ideal for showing proportions, because each bar is a different length. Sometimes, plotting relative values summing to 100% for each company may work better.
As it stands, the chart above calls attention to a different message: that Walmart dwarfs the other three global chains. Just the international income of Walmart is larger than the total income of Costco.
Please comment below or write me directly if you have ideas for this blog as we enter a new decade. What do you want to see more of? less of?
Thanks for all the interesting posts! I have learned a lot over the years.
I would love to see your opinion on this visual from AltMetric (the circular donut looking thing in the upper-left):
It appears alongside articles from the CDC all the time and I find it very confusing:
Keep up the stimulating work.
Posted by: Murphy | Jan 08, 2020 at 03:30 PM
Murphy: Thanks for the note. Will check it out.
Posted by: Kaiser | Jan 13, 2020 at 12:00 PM