What is a Pie Chart?
A pie chart is a circular chart divided into wedge-like sectors, illustrating proportion. Each wedge represents a proportionate part of the whole, and the total value of the pie is always 100 percent.
Pie charts can make the size of portions easy to understand at a glance. They're widely used in business presentations and education to show the proportions among a large variety of categories including expenses, segments of a population, or answers to a survey.
Pie Chart vs Bar Chart
Some critics of pie charts point out that the portions are hard to compare across other pie charts and if a pie chart has too many wedges, even wedges in a single pie chart are hard to visually contrast against each other compared to the height of bars in a bar graph for example.
Bar charts are easier to read when you're comparing categories or looking at change over time. The only thing bar charts lack is the whole-part relationship that makes pie charts unique. Pie charts imply that if one wedge gets bigger, the other has to be smaller. This would not be true of two bars on a bar chart.
How to Create a Pie Chart
Step one is making sure you have data formatted the correct way for a pie chart.
In the Insert tab in SmartDraw, click on Graph and choose Pie Chart..
Choose your data file to import and SmartDraw will automatically generate your graph.
Once imported, you can easily change the title, legend placement and even the quickly change the graph type using the Edit Graph options or just double-click on your imported chart.
Tips for Creating Better Pie Graphs
Don't use more than 5 slices in any pie chart otherwise it becomes too hard to read.
Don't use a pie chart if the values of the wedges are close to each other and it's important to see the differences. For example, 32%, 33% and 35% will look pretty even at a glance when illustrated on a pie chart. Using a bar chart will make the differences more obvious.
Don't use a pie chart if what you're comparing are not parts of a whole. For example, it makes sense to use a pie chart to compare the profitability of different divisions inside a larger enterprise. However, it doesn't make sense to compare different companies using a pie chart since there's a much larger number of companies and they don't belong to any meaningful whole.
Categories on the pie chart must be mutually exclusive and not overlapping.
History of Pie Charts
Pie charts have been around since the 1800s when they were used to illustrate statistics and maps.
Florence Nightingale popularized the pie chart as a form of persuasion using statistics by calling attention to the mortality rates caused by poor sanitary conditions during the Crimean war.
How Does a Donut Chart Compare to a Pie Chart
Donut charts are similar to pie charts in that their aim is to illustrate proportions. However, they contain a blank center that can contain a description or another layer of information.
Another variation of a pie chart is known as a ring chart. A ring chart, also known as a sunburst chart, is a multi-layered donut chart with many rings to represent hierarchies of data in concentric circles.