Pie & Donut Charts
Part-to-Whole Charts (Pie & Donut)
What Is This Report Type?
Pie and Donut Charts are circular statistical graphics divided into slices to illustrate numerical proportions. In a Pie Chart, the arc length of each slice is proportional to the quantity it represents. A Donut Chart is similar but has a blank center, creating a ring-like appearance that can house a summary metric.
Why Is It Used?
These charts are used to show “part-to-whole” relationships. They are most effective when you want to compare a small number of categories (usually 2–6) to see how they contribute to a total value.
Key Features and Characteristics
| Feature | Description |
|---|---|
| Proportional Representation | Instantly visualizes the relative size of different segments within a 100% total. |
| Donut Hole Variation | Adjustable inner radius creates a Donut chart that can house a total value or key metric in the center. |
| Segment Highlighting | ”Slice Exploding” feature pulls a specific slice away from the center for emphasis. |
| Smart Grouping | Automatically groups numerous small categories into a single “Other” slice to maintain readability. |
When to Use It (Use Cases)
- Market Share: Comparing your company’s revenue against its top 3 competitors.
- Budget Allocation: Visualizing the percentage of budget spent across different departments (HR, IT, Marketing).
- Customer Demographics: Showing the distribution of users by plan type (Bronze, Silver, Gold).
- Device Usage: Seeing the percentage of traffic from Mobile, Desktop, and Tablet.
Real-Time Business Example
Scenario: A CFO wants to review the company’s annual technology spend by category.
Visualization: A Donut Chart where each segment represents a category (Cloud Hosting, Software Licenses, Hardware, IT Consulting). The center of the donut displays “Total Spend: $1.2M”. This allows the CFO to quickly see that Cloud Hosting accounts for the largest portion (45%) of the IT budget.
Common Metrics Displayed
- Percentage of Total: The relative weight of a category.
- Absolute Values: The raw numerical value behind each slice.
- Market Concentration: How few or many categories dominate the total.
User Interactions
| Interaction | Behavior |
|---|---|
| Filters | Use “Top N” filters to limit the chart to the most significant segments. |
| Drill-Down | Clicking a slice updates the rest of the dashboard to show details only for that specific category. |
| Export | Export to Excel. |
Related Documentation
- Donut — Detailed guide for Donut charts with center metrics and segment analysis.
Creation Steps
- Select Pie or Donut Chart.
- Group By: Drag a category field.
- Metrics: Drag the value field. (Note: Pie charts are best for 5 or fewer categories.)