{
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "config": {
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        }
    },
    "data": {
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            "parse": {
                "Date": "utc:'%Y-%m-%d'"
            }
        },
        "url": "https://vega.github.io/vega-lite/data/co2-concentration.csv"
    },
    "description": "Carbon dioxide in the atmosphere.",
    "encoding": {
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            "axis": {
                "tickCount": 10,
                "title": "Year into decade",
                "values": [
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                    2,
                    3,
                    4,
                    5,
                    6,
                    7,
                    8,
                    9
                ]
            },
            "field": "scaled_date",
            "type": "quantitative"
        },
        "y": {
            "axis": {
                "title": "CO₂ concentration in ppm"
            },
            "field": "CO2",
            "scale": {
                "zero": false
            },
            "type": "quantitative"
        }
    },
    "height": 500,
    "layer": [
        {
            "encoding": {
                "color": {
                    "field": "decade",
                    "legend": null,
                    "type": "nominal"
                }
            },
            "mark": {
                "orient": "vertical",
                "type": "line"
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            "encoding": {
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                    "field": "aggregated.year",
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                "dx": 3,
                "dy": 1,
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                    "as": "scaled_date",
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                {
                    "as": "CO2",
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                    "type": "nominal"
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                "align": "left",
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            "calculate": "month(datum.Date)"
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            "calculate": "floor(datum.year / 10)"
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            "as": "scaled_date",
            "calculate": "(datum.year % 10) + (datum.month / 12)"
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