{
    "transform": [
        {
            "window": [
                {
                    "op": "sum",
                    "as": "sum",
                    "field": "amount"
                }
            ]
        },
        {
            "window": [
                {
                    "op": "lead",
                    "as": "lead",
                    "field": "label"
                }
            ]
        },
        {
            "as": "lead",
            "calculate": "datum.lead === null ? datum.label : datum.lead"
        },
        {
            "as": "previous_sum",
            "calculate": "datum.label === 'End' ? 0 : datum.sum - datum.amount"
        },
        {
            "as": "amount",
            "calculate": "datum.label === 'End' ? datum.sum : datum.amount"
        },
        {
            "as": "text_amount",
            "calculate": "(datum.label !== 'Begin' && datum.label !== 'End' && datum.amount > 0 ? '+' : '') + datum.amount"
        },
        {
            "as": "center",
            "calculate": "(datum.sum + datum.previous_sum) / 2"
        },
        {
            "as": "sum_dec",
            "calculate": "datum.sum < datum.previous_sum ? datum.sum : ''"
        },
        {
            "as": "sum_inc",
            "calculate": "datum.sum > datum.previous_sum ? datum.sum : ''"
        }
    ],
    "height": 450,
    "data": {
        "values": [
            {
                "amount": 4000,
                "label": "Begin"
            },
            {
                "amount": 1707,
                "label": "Jan"
            },
            {
                "amount": -1425,
                "label": "Feb"
            },
            {
                "amount": -1030,
                "label": "Mar"
            },
            {
                "amount": 1812,
                "label": "Apr"
            },
            {
                "amount": -1067,
                "label": "May"
            },
            {
                "amount": -1481,
                "label": "Jun"
            },
            {
                "amount": 1228,
                "label": "Jul"
            },
            {
                "amount": 1176,
                "label": "Aug"
            },
            {
                "amount": 1146,
                "label": "Sep"
            },
            {
                "amount": 1205,
                "label": "Oct"
            },
            {
                "amount": -1388,
                "label": "Nov"
            },
            {
                "amount": 1492,
                "label": "Dec"
            },
            {
                "amount": 0,
                "label": "End"
            }
        ]
    },
    "width": 800,
    "$schema": "https://vega.github.io/schema/vega-lite/v3.json",
    "layer": [
        {
            "mark": {
                "size": 45,
                "type": "bar"
            },
            "encoding": {
                "color": {
                    "value": "#93c4aa",
                    "condition": [
                        {
                            "value": "#f7e0b6",
                            "test": "datum.label === 'Begin' || datum.label === 'End'"
                        },
                        {
                            "value": "#f78a64",
                            "test": "datum.sum < datum.previous_sum"
                        }
                    ]
                },
                "y2": {
                    "field": "sum"
                },
                "y": {
                    "field": "previous_sum",
                    "title": "Amount",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "x2Offset": 22.5,
                "strokeWidth": 2,
                "color": "#404040",
                "opacity": 1,
                "xOffset": -22.5,
                "type": "rule"
            },
            "encoding": {
                "x2": {
                    "field": "lead"
                },
                "y": {
                    "field": "sum",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "dy": -8,
                "color": "#404040",
                "type": "text",
                "fontWeight": "bold"
            },
            "encoding": {
                "text": {
                    "field": "sum_inc",
                    "type": "nominal"
                },
                "y": {
                    "field": "sum_inc",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "dy": 8,
                "color": "#404040",
                "type": "text",
                "baseline": "top",
                "fontWeight": "bold"
            },
            "encoding": {
                "text": {
                    "field": "sum_dec",
                    "type": "nominal"
                },
                "y": {
                    "field": "sum_dec",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "type": "text",
                "baseline": "middle",
                "fontWeight": "bold"
            },
            "encoding": {
                "color": {
                    "value": "white",
                    "condition": {
                        "value": "#725a30",
                        "test": "datum.label === 'Begin' || datum.label === 'End'"
                    }
                },
                "text": {
                    "field": "text_amount",
                    "type": "nominal"
                },
                "y": {
                    "field": "center",
                    "type": "quantitative"
                }
            }
        }
    ],
    "encoding": {
        "x": {
            "field": "label",
            "sort": null,
            "title": "Months",
            "type": "ordinal"
        }
    },
    "description": "Waterfall chart of monthly profit and loss"
}