{ "transform": [ { "filter": "datum.symbol === 'GOOG'" } ], "data": { "url": "https://vega.github.io/vega-lite/data/stocks.csv" }, "$schema": "https://vega.github.io/schema/vega-lite/v4.json", "layer": [ { "mark": { "opacity": 0.3, "type": "point" }, "encoding": { "x": { "field": "date", "timeUnit": "year", "type": "temporal" }, "y": { "field": "price", "type": "quantitative" } } }, { "mark": "line", "encoding": { "x": { "field": "date", "timeUnit": "year", "type": "temporal" }, "y": { "field": "price", "aggregate": "mean", "type": "quantitative" } } } ], "description": "Plot showing average data with raw values in the background." }