The case for a Pie Charts – Fall 20 Data Visualizations and Narratives

Pie charts are excellent for expressing proportions, especially those that have percentages. Pie charts tell a whole story but then divide it into smaller segments to better understand and visualize what the story is trying to portray. The best way to use pie charts is when expressing 2 to 6 different categories. A pie chart can be used to express the percentages of people with heart disease and those without, or people with BMW and those with Sudan. Pie Charts are most effective if labeled correctly, have few slices, and the colors show each slice with good contrast.

There are good Pie Charts, and there are poor quality pie charts.

*https://www.esri.com/arcgis-blog/products/product/mapping/pie-charts-dos-and-donts/*

There are also different types of Pie Charts to represent data, depending on the type of data and how someone wants their data to be displayed.

*This pie chart is sliced into three sections to portion out the data. It gives the audience a visual of how big the percentage is.*

*This donut pie chart has a hole in the middle to separate the slices, which allow the audience to pull the slices apart and analyze it.*

Why Don't People Vote? (UPDATE) - Sociological Images — *The colors used in this pie chart represent the slices and their data clearly. The numbers are organized in a clockwise direction and are in order with the legend,* *making it easy to understand and read.*

This is the same data as in the pie chart to the left. The data is best represented in a pie chart because with the pie chart, the slices give the audience a better visual of how many percentage or number.

These are some websites explaining how to effectively use pie charts and when it should be used:

https://www.esri.com/arcgis-blog/products/product/mapping/pie-charts-dos-and-
donts/http://www.storytellingwithdata.com/blog/2020/5/14/what-is-a-pie-chart