I am developing a new seminar aimed at business professionals who want to improve their ability to communicate using charts. I want any guidance to be tool-agnostic, so that attendees can implement them using Excel if that’s their main charting software. Over the 12+ years that I’ve been blogging, certain ideas keep popping up; and I have collected these motifs and organized them for the seminar. This post is about a recent chart that brings up a few of these motifs.
This chart has been making the rounds in articles about the steel tariffs.
The chart shows the Top 10 nations that sell steel to the U.S., which together account for 78% of all imports.
The chart shows a few signs of design. These things caught my eye:
- the pie chart on the left delivers the top-line message that 10 countries account for almost 80% of all U.S. steel imports
- the callout gives further information about which 10 countries and how much each nation sells to the U.S. This is a nice use of layering
- on the right side, progressive tints of blue indicate the respective volumes of imports
On the negative side of the ledger, the chart is marred by three small problems. Each of these problems concerns inconsistency, which creates confusion for readers.
- Inconsistent use of color: on the left side, the darker blue indicates lower volume while on the right side, the darker blue indicates higher volume
- Inconsistent coding of pie slices: on the right side, the percentages add up to 78% while the total area of the pie is 100%
- Inconsistent scales: the left chart carrying the top-line message is notably smaller than the right chart depicting the secondary message. Readers’ first impression is drawn to the right chart.
Easy fixes lead to the following chart:
The central idea of the new dataviz seminar is that there are many easy fixes that are often missed by the vast majority of people making Excel charts. I will present a stack of these motifs. If you're in the St. Louis area, you get to experience the seminar first. Register for a spot here.
Send this message to your friends and coworkers in the area. Also, contact me if you'd like to bring this seminar to your area.
I also tried the following design, which brings out some other interesting tidbits, such as that Canada and Brazil together sell the U.S. about 30% of its imported steel, the top 4 importers account for about 50% of all steel imports, etc. Color is introduced on the chart via a stylized flag coloring.