Math — Chart: Pie Chart

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "description": "Budget split",
  "data": {"values": [
    {"category": "Housing", "share": 35},
    {"category": "Food", "share": 20},
    {"category": "Transport", "share": 15},
    {"category": "Savings", "share": 18},
    {"category": "Other", "share": 12}
  ]},
  "mark": "arc",
  "encoding": {
    "theta": {"field": "share", "type": "quantitative"},
    "color": {"field": "category", "type": "nominal", "title": "Category"}
  }
}