{
    "transform": [
        {
            "joinaggregate": [
                {
                    "op": "sum",
                    "as": "TotalTime",
                    "field": "Time"
                }
            ]
        },
        {
            "as": "PercentOfTotal",
            "calculate": "datum.Time/datum.TotalTime * 100"
        }
    ],
    "mark": "bar",
    "data": {
        "values": [
            {
                "Time": 8,
                "Activity": "Sleeping"
            },
            {
                "Time": 2,
                "Activity": "Eating"
            },
            {
                "Time": 4,
                "Activity": "TV"
            },
            {
                "Time": 8,
                "Activity": "Work"
            },
            {
                "Time": 2,
                "Activity": "Exercise"
            }
        ]
    },
    "$schema": "https://vega.github.io/schema/vega-lite/v3.json",
    "encoding": {
        "x": {
            "field": "PercentOfTotal",
            "type": "quantitative",
            "axis": {
                "title": "% of total Time"
            }
        },
        "y": {
            "field": "Activity",
            "scale": {
                "rangeStep": 12
            },
            "type": "nominal"
        }
    }
}