{
  "data": {"name": "dataset"},
  "transform": [
    {
      "window": [
        {
          "op": "max",
          "field": "# Engagements",
          "as": "max_value"
        }
      ]
    },
    {
      "calculate": "(datum.max_value - datum.value)/2",
      "as": "start"
    },
    {
      "calculate": "datum.start + datum.value",
      "as": "end"
    }
  ],
  "layer": [
    {
      "mark": {
        "type": "bar",
        "opacity": 0.3,
        "tooltip": true
      },
      "encoding": {
        "y": {"field": "# Engagements"}
      }
    },
    {
      "mark": {
        "type": "bar",
        "tooltip": true
      },
      "encoding": {
        "y": {
          "field": "# Engagements__highlight"
        },
        "opacity": {
          "condition": {
            "test": {
              "field": "__selected__",
              "equal": "off"
            },
            "value": 0
          },
          "value": 1
        }
      }
    }
  ],
  "encoding": {
    "x": {
      "field": "Engagement Type",
      "type": "nominal"
    },
    "y": {
      "type": "quantitative",
      "axis": {"title": "# Engagements"}
    }
  }
}