1. The art of data visualization
Hi there! By now, you have probably realized that building charts in Excel isn't difficult. Let's now focus on charting best practices so that our visualizations look stunning and insightful.
2. When less is more
With charts, less is often more. Let's examine two visualizations of banana exports by the top countries between 1994 and 2005. Can you tell which one is more insightful?
While both can be created with just a few clicks in Excel, the chart on the right has a clear advantage in terms of clarity, drawing conclusions, and providing immediate insights. What makes it superior? As you will learn in this chapter, creating a visually appealing and insightful chart requires making several decisions. Let's review the dos and don'ts one by one.
3. Two dimensions OR three dimensions?
When exploring various Excel chart types, it surely didn't escape your attention that many 3D chart variants exist. However, one of the best data visualization practices is keeping things simple. Excel still offers this option to prevent older files that have 3D charts from crashing, so it's more of a legacy and backward compatibility feature than anything we should consider using.
3D charts are hard to read and make interpreting the data difficult. As 3D charts create a perspective that distorts the vision and confuses the eye, the best advice is to avoid using them. 2D charts offer an easily interpretable alternative. They are versatile and do not distract from what matters - the data.
4. Labels, legends, and titles
Secondly, ensuring that our charts are as self-explanatory as possible is crucial. The chart on the left lacks several elements, such as chart and axes titles, and is therefore impossible to understand.
Furthermore, the axis does not start at 0, which may lead to wrong chart interpretations. The chart on the right contains all essential elements, such as clear axes, labels, and an informative title. Y-axis starts at zero and is no longer misleading.
5. Color: an ally or enemy?
Another important and often misused element of charts is color. Color draws attention and should be used intelligently. In the example on the left, the color adds no extra value. Moreover, certain colors, like red, amber, and green, have specific associations (green for good, red for bad). Therefore, these should not be used as categorical colors in a chart like this one.
The chart would look much better if all bars were of the same color or if only one bar, such as the top one, was highlighted in a different color to draw attention to the highest value. Highlighting the key message in the title is also a good idea.
6. The Great Chart Cleanse - decluttering of charts
Another good practice is to remove clutter from the chart. Looking at the left chart, you will quickly notice that certain elements are redundant. The numerical denominator, "millions," is mentioned thrice. The legend "total" is unnecessary, as is the year axis title.
Evaluating each chart element and determining if it contributes to the overall chart would be much better. Remember that less is often more.
7. Accentuating the main message like a pro
Next, use all chart elements and characteristics to your advantage. Self-explanatory charts utilize titles and colors to draw attention to the main message while avoiding unnecessary labels that may distract. Limiting the number of data points and reducing the focus or graying out the less important ones is also beneficial.
8. The lost art of "chartology": choosing the perfect graph
Finally, what are the other good practices for data visualizations? Always choose the correct chart type! Did you know there are one or more suitable charting options for every use case? Consider trying out various chart variants and get inspired by the numerous resources available online. Two of the most notable ones are our very own DataCamp data viz cheat sheet and the 'Storytelling with Data' blog and book. Check them out!
9. Let's practice!
It takes some experimenting to find the best chart, but we will have plenty of opportunities to practice in this chapter.