{
  "schema_version": 1,
  "chart_type": "proportion",
  "mark": "donut",
  "meta": {
    "title": "Signup Traffic by Source",
    "quality_profile": "showcase"
  },
  "data": {
    "columns": [
      { "id": "source", "type": "string", "values": ["Organic search", "Direct", "Referral", "Paid social", "Email", "Other"] },
      { "id": "signups", "type": "number", "unit": "signups", "values": [4820, 2310, 1640, 980, 610, 340] }
    ]
  },
  "encoding": {
    "category": { "column": "source" },
    "value": { "column": "signups" }
  },
  "cards": [
    { "title": "Takeaway", "items": ["Organic search brings 45.0% of signups — more than Referral, Paid social, and Email combined.", "Email is the smallest named channel outside the Other bucket at 610 signups (5.7%)."] }
  ]
}