line7.vl

{
    "mark": {
        "point": true,
        "type": "line"
    },
    "data": {
        "url": "https://vega.github.io/vega-lite/data/driving.json"
    },
    "$schema": "https://vega.github.io/schema/vega-lite/v3.json",
    "encoding": {
        "x": {
            "field": "miles",
            "scale": {
                "zero": false
            },
            "type": "quantitative"
        },
        "order": {
            "field": "year",
            "type": "temporal"
        },
        "y": {
            "field": "gas",
            "scale": {
                "zero": false
            },
            "type": "quantitative"
        }
    },
    "description": "A connected scatterplot can be created by customizing line order and adding point marker in the line mark definition."
}