Data Visualization, Microsoft Technologies, Power BI

CDOT Bar Chart Makeover

As I was browsing Twitter today, I noticed a tweet from the Colorado Department of Transportation about their anti-DUI campaign. Shown below, it contains a bar chart that appears to have been presented in PowerPoint.

Tweet from CDOT containing a poorly designed bar chart

There are some easy opportunities to improve the readability of this chart, so I thought I would use it as an example of how small improvements can have a big impact on a fairly simple chart. I recreated the chart (as best I could) in Power BI and then made two revised versions.

Bar chart with 5 bars representing suspected impaired driving fatalities per year. The top left contains 3 logos. The title is on the top right. Each bar is a different bright color. The axis labels are very small.
My Power BI version of the original chart
Redesigned bar chart that removes the thick orange line, moves the title to the top left, and uses only one color across the bars.
My 10-minute makeover that increased readability
Bar chart with red bars and an annotation noting the upward trend from 2019 to 2020. A gray placeholder with a question mark has been added for 2021 with the note "Don't become part of this statistic."
My additional iteration that applied a clearer message and focus

Especially when making data visualizations for the general public —and especially when you want to get people’s engagement on social media— you need to reduce perceived cognitive load. Otherwise, people won’t even bother to read your chart. If your chart feels too busy or too complicated, many people in your intended audience will feel it is not worth the effort to even try to read it and will move on down their Twitter feed to the next Anakin and Padme meme.

Watch the video below for all of the details.

21-minute video showing how to improve upon a bar chart found on Twitter using Power BI