NOTE: This is the third post in our Windward series on creating beautiful reports. Missed the beginning? Start here.
Charts can be some of the most beautiful elements of a report, especially when compared to plain black and white text or tables that are jam-packed with data.
So why is that too often, charts are so darn ugly?
It doesn’t have to be this way. Even if your strength is data and not report design, you can create informative, beautiful report charts that wow your audience.
Before You Begin
Step away from the keyboard and ask yourself two important questions.
ONE: Am I conveying many individual data points, or am I trying to show an overall trend instead?
As we discussed in our earlier post What Makes a Beautiful Report: Tables, if it’s important that the report reader see the individual data points, go with a table. If not, you’ll likely want a chart.
The illustration below shows a clear example of when you might prefer charts to tables. First, a table showing 2014 Eurovision voting from the Azerbaijan jurors (view original post):
Can you immediately spot any trends? Probably not. But it’s a lot easier to see with the data laid out in a chart:
The chart makes it readily apparent that the five jurors appear to show voter collusion, as evidenced by the tight grouping of the data. (View the original post, written by Windward’s founder and CTO, David Thielen.)
TWO: What is the purpose of my chart?
Is it to enable the report viewer to identify one key trend? Compare a variety of information points? Allow for many layers of data or just a single one? Think about the purpose of the chart first so you know what you want to display and highlight.
Once you’ve got that figured out, you’re ready to dig into designing beautiful charts.
Choose the Correct Chart Type
Take a look at the chart on the left. Notice anything odd about it?
That’s right; the values don’t add up to 100%. This violates a basic principle of chart design, where viewers expect pie charts to show how large a slice of one pie – what percentage of the whole – a particular data group “eats.” In this case, a bar chart would have been more appropriate.
Hubspot’s fantastic guide Data Visualization 101: How to Design Charts and Graphs provides details on when to use each chart type and offers some design best practices for each.
Place Elements Appropriately
There are standard conventions for placing elements on a chart. For example:
- Numbers along axes typically go from small to large, or from oldest to newest in the case of dates.
- For pie charts with dozens of tiny slices, group the tiny slices into an “other” category so as not to overwhelm the reader with irrelevant information.
- When labeling data points, don’t show them all; show just a few where notable events happened.
When you don’t follow these conventions, bad things happen. Check out the chart on the right. At first, you likely think that gun deaths in Florida went down after Florida enacted the “stand your ground” law. But look again at the Y axis, and you’ll see a different story.
For more on misleading charts, check out this excellent article, How to Lie with Data Visualization.
Data geeks – we get it. You love data and you love showing lots of facts and figures. But sometimes, you need to hold yourself back.
This is often the case with chart size. Bigger charts aren’t more impressive; they’re just bigger. With a smaller chart, the person viewing the report can pick up key information and see the chart in context with other report elements around it.
A good rule of thumb is to make the chart as large as it needs to be in order for the text to be legible and not much larger.
Use Effects Sparingly
You’re probably using some sort of reporting software to generate your charts, which means you have some cool visual effects you can apply with a button push. And you probably have.
Whoa, Nelly. Before you choose the next effect to “spice” up your chart, remember what mama used to say: just because you can doesn’t mean you should. Bevel effects, shape outlines and trend lines may sound good in theory, but look what happens when you put them into practice. You go from this:
Remember that visual effects should enhance your numbers, not detract from them.
NOTE: We generated the above chart examples with the Microsoft® Office add-in Windward AutoTag.
Highlight Key Data
A chart, just like a paragraph, should focus on one main idea. If that idea can be conveyed in one sentence, great. If not, use visual cues to highlight key information. (See what we just did there?)
For instance, you can add “weight” (aka thickness) to a set of data points in a line graph when you want to call out a particular series, such as we do in the chart below:
Pay Close Attention to Color
There are millions of colors out there, which means either:
a. You have zillions of wonderful possibilities to create (for you glass-half-full types), or
b. You have zillions of ways to screw it up (for you glass-half-empty types).
Fortunately, there are several principles to help guide your color choices. Here are three key ones:
- Conventional color combinations. Data can immediately convey information based solely on color choice, and it’s something you likely learned as a kid on the playground. “Red light, green light” ring a bell? When used together, green means go, yellow means slow and red means stop. Red and black ink when used with numbers/currency is another charts convention. (But remember that those with color blindness may have difficulty with certain combinations, especially red/green, so use helpful cues such as text.)
- Predetermined color combinations. The software you are using to create your chart likely offers a range of options you can choose from. Spend a couple minutes trying a few out for size, and if they all look the same to you, ask a colleague for a second opinion.
- Company logos. Ever wonder what your marketing department does all day? We don’t know either, but one thing they’ve likely done is create a company logo – and they paid very close attention to colors and color combinations when doing so. Take advantage of that knowledge by using those colors, when appropriate, in your charts to reinforce your brand.
The Whole Beautiful Report Series
Also, we want to thank your for reading this series on how to design beautiful reports. We have released the entire series as a free e-book for you to download, share and refer to in the future.
Remember, you can receive the series in your email inbox by subscribing to our company blog here:
Author: Heidi V. Anderson
Heidi has been writing professionally about computers, technology and the Internet for more than 20 years. She lives in Vermont where she taps her maple trees for syrup and most of the year wishes it was just a little bit warmer out.
Other posts by Heidi V. Anderson