Comet Chart Deneb

Comet.json

{
    "data": {"name": "dataset"},
    "title": "Change In Percent of Americans Living Alone - 1980 vs 2018",
    "height": 40,
    "width": 350,
    "mark": {"type": "trail"}, 
  "encoding": {
    "facet": {
      "field": "Entity",
      "title": null,
      "type": "nominal", 
      "columns": 1, 
      "spacing": 1, 
      "align": "all", 
      "center": false, 
      "spacing": 1,
      "header": {"labelAlign": "left", 
      "labelAnchor": "middle", "labelOrient": "left",
      "labelBaseline": "top", "labelAngle": 0}
    },
    "x": { 
      "field": "Percent Living Alone", "type": "quantitative", 
      "title": null
    },
    "size": {
      "field": "Size", 
      "type": "quantitative",
      "scale": {"range": [1, 8]},
      "legend": false
    },
      "color": {
      "field": "PctDelta Sign",
      "type": "quantitative",
      "scale": {"domainMid": 0},
      "title": "Change In Pct", 
      "legend": false
  }
  
}
}