Charts / CH-PTW-09
CH-PTW-09 . family PTW

SUNBURST

two concentric rings: groups inside, children outside. Needs: a strict 2-level hierarchy: 2-4 groups, 2-4 children each.

part-to-wholecomposition

DL-01 AGRAW
Installation work holds 52% of remaining hours Install Mechanical 24% Electrical 18% Piping 10% Test Loops 16% Systems 12% Docs As-built 12% Handover 8% Source: sample dataset v1, 2026-07-12

Use when

  • WARN: only when a 2-level whole must be shown in one figure
  • hierarchical composition where both levels matter at once

Do not use when

  • angle comparison across rings (humans cannot)
  • more than 2 levels (unreadable)
  • small shares (labels vanish)

See instead

Alternatives

  • CH-PTW-05 (one level, honest areas)
  • CH-PTW-01 (few parts, exact)

Rules

  • exactly two rings; children sum to their group
  • shares printed on outer labels; tiny slices stay silent
  • groups colored by the monochrome ramp, children by a lighter mix

Never do this

  • WARN ENTRY: a treemap (CH-PTW-05) answers the same question with readable areas
  • 3+ rings
  • rainbow slices
  • donut-hole KPIs stuffed in the middle

QA before delivering

  • two rings exactly
  • children sum to groups
  • shares printed where they fit
  • source present

Data shape

titleaction title with a number
sourcebottom-left always
unitshare unit
groups[{name, children: [{name, value}]}]
Sample data (golden) 
{
  "title": "Installation work holds 52% of remaining hours",
  "eyebrow": "REMAINING HOURS",
  "source": "Source: sample dataset v1, 2026-07-12",
  "unit": "%",
  "groups": [
    {
      "name": "Install",
      "children": [
        {
          "name": "Mechanical",
          "value": 24
        },
        {
          "name": "Electrical",
          "value": 18
        },
        {
          "name": "Piping",
          "value": 10
        }
      ]
    },
    {
      "name": "Test",
      "children": [
        {
          "name": "Loops",
          "value": 16
        },
        {
          "name": "Systems",
          "value": 12
        }
      ]
    },
    {
      "name": "Docs",
      "children": [
        {
          "name": "As-built",
          "value": 12
        },
        {
          "name": "Handover",
          "value": 8
        }
      ]
    }
  ]
}