line4.vl

{
    "mark": "line",
    "data": {
        "url": "https://vega.github.io/vega-lite/data/barley.json"
    },
    "width": {
        "step": 50
    },
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "encoding": {
        "color": {
            "field": "site",
            "type": "nominal"
        },
        "x": {
            "field": "year",
            "scale": {
                "padding": 0.5
            },
            "type": "ordinal"
        },
        "y": {
            "field": "yield",
            "aggregate": "median",
            "type": "quantitative"
        }
    },
    "description": "Slope graph showing the change in yield for different barley sites. It shows the error in the year labels for the Morris site."
}