Math — Chart: Disease Incidence Trend

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "description": "Incidence per 100,000",
  "data": {"values": [
    {"year": 2015, "rate": 52},
    {"year": 2016, "rate": 48},
    {"year": 2017, "rate": 45},
    {"year": 2018, "rate": 40},
    {"year": 2019, "rate": 36},
    {"year": 2020, "rate": 30}
  ]},
  "mark": {"type": "line", "point": true},
  "encoding": {
    "x": {"field": "year", "type": "ordinal", "title": "year"},
    "y": {"field": "rate", "type": "quantitative", "title": "incidence per 100k"}
  }
}