100% Stacked Area

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    "interactivity": {
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      "selection": false,
      "highlight": false,
      "dataPointLimit": 50
    },
    "information": {
      "name": "100% Stacked Interactive Hover",
      "description": "[No Description Provided]",
      "author": "Kerry Kolosko",
      "uuid": "d9061995-d5bd-4b7f-b1e8-638613a9f571",
      "generated": "2022-06-26T14:24:45.594Z"
    },
    "dataset": [
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        "key": "__0__",
        "name": "Year",
        "description": "",
        "type": "numeric",
        "kind": "column"
      },
      {
        "key": "__1__",
        "name": "Category",
        "description": "",
        "type": "text",
        "kind": "column"
      },
      {
        "key": "__2__",
        "name": "Value",
        "description": "",
        "type": "numeric",
        "kind": "measure"
      }
    ]
  },
  "config": {
    "autosize": {
      "type": "fit",
      "contains": "padding"
    },
    "view": {"stroke": "transparent"},
    "font": "Segoe UI",
    "arc": {},
    "area": {
      "line": false,
      "opacity": 1
    },
    "bar": {},
    "line": {
      "strokeWidth": 3,
      "strokeCap": "round",
      "strokeJoin": "round"
    },
    "path": {},
    "point": {
      "filled": true,
      "size": 75
    },
    "rect": {},
    "shape": {},
    "symbol": {
      "strokeWidth": 1.5,
      "size": 50
    },
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      "fontSize": 12,
      "fill": "#605E5C"
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    "legend": {
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      "labelFont": "Segoe UI",
      "labelFontSize": 13.333333333333332,
      "labelColor": "#605E5C",
      "symbolType": "circle",
      "symbolSize": 75
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  },
  "data": {"name": "dataset"},
  "params": [
    {
      "name": "genres",
      "select": {
        "type": "point",
        "on": "mouseover",
        "fields": ["__1__"]
      },
      "bind": "legend"
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  ],
  "mark": {
    "type": "area",
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  },
  "encoding": {
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      "type": "ordinal",
      "axis": {
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        "labelAlign": "left",
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        "labelOffset": 4,
        "labelPadding": -24,
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        "values": [
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          "1970",
          "1980",
          "1990",
          "2000",
          "2010"
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      }
    },
    "y": {
      "aggregate": "sum",
      "field": "__2__",
      "axis": null,
      "stack": "normalize"
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    "color": {
      "field": "__1__",
      "scale": {"scheme": "category20"}
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    "opacity": {
      "condition": {
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