Data visualization communicates what is happening and why it is important. The best visualizations tell a simple story in a matter of seconds. The story has a designed impact to the listener.
![](https://plainlyresults.com/wp-content/uploads/2018/11/wisdom-92901_640-e1611519042631.jpg)
Here are listed three key practices to consider in data visualization, gathered by personal experience and online sources.
1. Is the story understood in seconds?
Look a graph or a dashboard for a couple of seconds. Make your friend look it for a couple of seconds. Do you understand its key point? What it tells about the business?
- Use mostly bar charts (comparison), line charts (trend), KPIs and matrix visualizations (either a table or e.g. matrix bubble chart). Use a pie chart with a lot of caution, it works best for two categories.
2. Make a standard layout
- Only a few aligned colors.
- One font with standard heading and label styles.
- Structured, repeating positioning of visual elements. Use filters pane in Power BI.
- Less is more. Keep graphics simple and consider making them even more simple than they are as a standard in Power BI.
- Labels in a graph are valuable for understanding. Most likely it makes sense to have a labeled axis, category labels and potentially some value labels. This improves the chances to understand a graph in a matter of seconds.
- Use standard icons to describe the functionality or the key topics in a page layout. Think how the best mobile app looks you know.
3. Data needs to be comparable
- Order the data in a meaningful way to tell a story.
- Scale it right. Especially line charts NOT starting from 0 axis are a dangerous tool. One month comparing 10 000 to 10 100 at the scale of 10 000 – 10 100 versus the scale of 0 to 15 000 sends quite a different message.
- Use the same units and time intervals across the whole dashboard as much as possible.
![Customer Churn % by Category and Reason](https://plainlyresults.com/wp-content/uploads/2021/01/graph_churn_reason.png)
Sources:
https://docs.microsoft.com/en-us/power-bi/create-reports/service-dashboards-design-tips
https://www.columnfivemedia.com/25-tips-to-upgrade-your-data-visualization-design
https://newprediction.com/free-data-visualization-books/
https://benfry.com/writing/