{
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "data": {
        "values": [
            {
                "city": "Bristol",
                "temperature": 12,
                "year": 2017
            },
            {
                "city": "Bristol",
                "temperature": 14,
                "year": 2018
            },
            {
                "city": "Sheffield",
                "temperature": 11,
                "year": 2017
            },
            {
                "city": "Sheffield",
                "temperature": 13,
                "year": 2018
            },
            {
                "city": "Glasgow",
                "temperature": 7,
                "year": 2017
            },
            {
                "city": "Glasgow",
                "temperature": 10,
                "year": 2018
            }
        ]
    },
    "encoding": {
        "x": {
            "field": "2017",
            "type": "quantitative"
        },
        "y": {
            "field": "city",
            "type": "nominal"
        }
    },
    "mark": "circle",
    "transform": [
        {
            "groupby": [
                "city"
            ],
            "pivot": "year",
            "value": "temperature"
        }
    ]
}