Trellis Area

{
  "$schema": "https://vega.github.io/schema/vega-lite/v2.json",
  "description": "Stock prices of four large companies as a small multiples of area charts.",
  "transform": [
      {
          "filter": "datum.symbol !== 'GOOG'"
      }
  ],
  "width": 300,
  "height": 40,
  "data": {
      "url": "data/stocks.csv"
  },
  "mark": "area",
  "encoding": {
      "x": {
          "field": "date",
          "type": "temporal",
          "axis": {
              "format": "%Y",
              "title": "Time",
              "grid": false
          }
      },
      "y": {
          "field": "price",
          "type": "quantitative",
          "axis": {
              "title": "Price",
              "grid": false
          }
      },
      "color": {
          "field": "symbol",
          "type": "nominal",
          "legend": null
      },
      "row": {
          "field": "symbol",
          "type": "nominal",
          "header": {"title": "Symbol"}
      }
  }
}