Interactive Legend

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Vega-Lite JSON Specification

{
  "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
  "width": 300, "height": 200,
  "data": {"url": "data/unemployment-across-industries.json"},
  "mark": "area",
  "selection": {
    "industry": {
      "type": "multi", "fields": ["series"], "bind": "legend"
    }
  },
  "encoding": {
    "x": {
      "timeUnit": "yearmonth", "field": "date", "type": "temporal",
      "axis": {"domain": false, "format": "%Y", "tickSize": 0}
    },
    "y": {
      "aggregate": "sum", "field": "count", "type": "quantitative",
      "stack": "center", "axis": null
    },
    "color": {
      "field":"series", "type": "nominal",
      "scale": {"scheme": "category20b"}
    },
    "opacity": {
      "condition": {"selection": "industry", "value": 1},
      "value": 0.2
    }
  }
}