{
    "transform": [
        {
            "groupby": [
                "age"
            ],
            "aggregate": [
                {
                    "op": "q1",
                    "as": "lowerBox",
                    "field": "people"
                },
                {
                    "op": "q3",
                    "as": "upperBox",
                    "field": "people"
                },
                {
                    "op": "median",
                    "as": "midBox",
                    "field": "people"
                }
            ]
        },
        {
            "as": "IQR",
            "calculate": "datum.upperBox - datum.lowerBox"
        },
        {
            "as": "upperWhisker",
            "calculate": "datum.upperBox + datum.IQR * 1.5"
        },
        {
            "as": "lowerWhisker",
            "calculate": "max(0,datum.lowerBox - datum.IQR *1.5)"
        }
    ],
    "data": {
        "url": "https://vega.github.io/vega-lite/data/population.json"
    },
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "layer": [
        {
            "mark": {
                "style": "boxWhisker",
                "type": "rule"
            },
            "encoding": {
                "y2": {
                    "field": "lowerBox"
                },
                "y": {
                    "field": "lowerWhisker",
                    "type": "quantitative",
                    "axis": {
                        "title": "Population"
                    }
                }
            }
        },
        {
            "mark": {
                "style": "boxWhisker",
                "type": "rule"
            },
            "encoding": {
                "y2": {
                    "field": "upperWhisker"
                },
                "y": {
                    "field": "upperBox",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "style": "box",
                "type": "bar"
            },
            "encoding": {
                "size": {
                    "value": 5
                },
                "y2": {
                    "field": "upperBox"
                },
                "y": {
                    "field": "lowerBox",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "style": "boxMid",
                "type": "tick"
            },
            "encoding": {
                "color": {
                    "value": "white"
                },
                "size": {
                    "value": 5
                },
                "y": {
                    "field": "midBox",
                    "type": "quantitative"
                }
            }
        }
    ],
    "encoding": {
        "x": {
            "field": "age",
            "type": "ordinal"
        }
    },
    "description": "A Tukey box plot showing median and interquartile range in the US population distribution of age groups in 2000. This isn't strictly a Tukey box plot as the IQR extends beyond the min/max values for some age cohorts."
}