PIE

Use when

• one dominant share against one or two others, single period
• the audience expects a pie and the data survives one (3 slices max)

Do not use when

• more than 3 categories (angles are unreadable; use CH-RNK-01)
• comparing shares across periods (CH-PTW-02)
• values close in size (angle differences under ~15% are invisible)

See instead

• more than 3 parts: CH-RNK-01
• shares tracked over time: CH-PTW-02

Alternatives

• CH-PTW-01 (stacked bar)
• CH-PTW-06 (waffle, planned)

Rules

• 3 slices maximum; the validator blocks a fourth
• slices sorted descending, first slice starts at 12 o'clock
• direct outside labels with the percentage; never a legend
• slice separators in the background color (2px)
• the largest slice takes primary; the rest recede

Never do this

• more than 3 slices
• 3D or exploded slices
• legends
• two pies side by side to show change (use CH-PTW-02)
• donut holes that carry no information (see CH-PTW-04's own warnings)

QA before delivering

• slices <= 3
• labels carry percentages, sum stated or reconciled in the title
• largest slice starts at 12 o'clock
• title states the dominant share with a number
• source line present bottom-left

Data shape

{
  "title": "Complete work holds 62% of total scope",
  "eyebrow": "SCOPE . WEEK 28",
  "source": "Source: sample dataset v1, 2026-07-12",
  "slices": [
    {
      "label": "Complete",
      "value": 62
    },
    {
      "label": "Remaining",
      "value": 28
    },
    {
      "label": "On hold",
      "value": 10
    }
  ]
}