Part of a whole
Circle-packing chart
Represents hierarchy through circle containment and values through circle areas.
- Chart
- Hierarchy
- Composition
What it answers
What groups contain which items and how large are they?
- Shape
- Nested circles
- What it shows
- Containment and dominant members.
Example
The question
How does revenue break down from category to product line?
Revenue by category and product line, EUR million (circle packing)
Illustrative data. It belongs to no company.
When to use it
Use it when
Exploring nested groups where structure matters more than precise totals.
Avoid it when
When unused packing space could be mistaken for missing data.
How to read it
Read containment for hierarchy and circle area for size.
Note
Packing gaps mean enclosing area is not a simple additive total.
The data you need
- Layout
- Parent-child table
- Fields
- NodeID: text; ParentID: text/blank; Label: text; Value: number when size is encoded
- One row is
- One node in a parent-child hierarchy. What is the grain?
- Rules
- Node IDs must be unique. Parents must exist. Reject cycles. Define leaf-only versus inclusive parent values.
- Optional
- Alternative: Level1,Level2...,Value. Tree diagrams can omit Value.
- Preparation
- Validate unique node IDs, parent links, roots and absence of cycles. For size-encoded hierarchies, state whether totals are leaf-only or inclusive.
- Units
- Tree levels and branch position are structural. Size-encoded components use a named value unit; parent shares divide by the chosen parent total.
Worked example
A contains circles of 20 and 40. Their enclosing circle also contains packing gaps, so its drawn area is not simply 60 equal area units.
| NodeID | ParentID | Label | Value |
|---|---|---|---|
| root | All | 100 | |
| a | root | A | 60 |
| b | root | B | 40 |