Glossary term
Pie Diagram: Meaning and Definition
Reviewed and approved by Dr. Anamika ShrivastavaPublished Last updated
A pie diagram is a circle divided into slices whose angles are proportional to the shares of the parts in a total. Since a full circle is 360 degrees, the angle of a slice is its share of the total multiplied by 360, or its percentage multiplied by 3.6 degrees.
In more detail
Pie diagrams show composition at a glance but are poor at showing small differences or changes over time. Slices are usually drawn clockwise, starting at twelve o’clock, and labelled with their shares. For comparing a few categories across years, a component bar diagram is clearer.
Example
If farming gives 45 per cent of a village’s income, its slice is 45 × 3.6 = 162 degrees.
Key points
- Angle = (value ÷ total) × 360°.
- Angles must add to 360°.
- Suits few categories; use a bar chart for many.
Common mistake
Using a pie diagram for data that are not parts of a whole.
Related terms
HistogramFrequency distribution
Where it is explained
This term is explained in Class 11 Statistics Chapter 4: Presentation of Data.