The main purpose of a chart is to help people understand and compare. Our charts should be:
- Useful. To help people understand a chart, we pair data with interpretation.
- Trustworthy. Include clear copy, including accurate labels, units, and timeframe.
- Based on behavioral science. Use charts to nudge people to change their behavior.
Creating a chart
Get your story straight, then choose the right format.
Articulate the concept
Before you start making a chart, figure out what you want to communicate. The same data can have different interpretations, so it’s up to you to decide what story to tell.
Choose the right format
Keep in mind that not every piece of data needs to be displayed in a chart—often, a simple table or other visual comparison will do.
Add insight or interpretation
Call out an interesting aspect of the data in a short sentence like so: Heating accounts for 36% of your energy use.
Double-check the details
Include in all chart types:
- Heading (descriptive, use sentence case)
- Units of measurement
- Reference to time
- Insight or interpretation
Depending on the content, charts can also have:
- Related body copy
What type of chart to use
|Bar and column chart||Line chart and area chart||Pie chart|
|Best for…||Comparing using same characteristic
Changes over time
|Emphasis on…||Relative size of bars||Relationship between points
Peaks and valleys
|Relative size of slices|
|Pros||Easy to compare||Shows lots of data at once
|Cons||Can be hard to compare slices|