Less is often more. Here are ten lessons we've learned about how to better communicate with data by giving readers less.
1. Reduce chart junk. Edward Tufte taught us this fundamental lesson. Eliminate elements on a chart that aren't contributing to comprehension.
2. Reduce color. Instead of using a rainbow of colors, pick an emphasis color and use color with clear purpose and consistent meaning.
3. Reduce jargon. Consider how your audience speaks in their everyday work. Are there more natural ways of expressing your points?
4. Reduce pie charts. They are seldom the most effective way to show your data, and pie charts can often be misleading or difficult to interpret.
5. Reduce unnecessary precision. Provide enough precision in your number formats to tell the difference between values and shorten numbers to make the values more readable (e.g. MM, k).
6. Reduce metrics. "Data isn’t like your kids. You don’t have to pretend to love them equally." -- Amanda Cox, New York Times. Create constraints to show only the metrics that matter most.
7. Reduce density. It is a rare instance that all the relevant information needs to be crammed on the same page. Give your readers some whitespace to help them focus and comprehend the content.
8. Reduce dimensions. Individual visualizations quickly become difficult to interpret when many dimensions are shown simultaneously. If necessary, gradually "build" the visualization by adding complexity to ensure your audience can follow along.
9. Reduce quantity of messages. It can be tempting to try to tell numerous stories about data at the same time. Try to tell them one at a time to help each one land with the audience.
10. Reduce chart types. It can be tempting to use different types of charts as a way to add variety to a report or dashboard. In the process, you are putting a burden on your audience to learn how to interpret each new chart.