chart = {
const width = 928;
const height = 500;
const marginTop = 10;
const marginRight = 10;
const marginBottom = 20;
const marginLeft = 40;
const series = d3.stack()
.keys(d3.union(data.map(d => d.age)))
.value(([, D], key) => D.get(key).population)
(d3.index(data, d => d.state, d => d.age));
const x = d3.scaleBand()
.domain(d3.groupSort(data, D => -d3.sum(D, d => d.population), d => d.state))
.range([marginLeft, width - marginRight])
.padding(0.1);
const y = d3.scaleLinear()
.domain([0, d3.max(series, d => d3.max(d, d => d[1]))])
.rangeRound([height - marginBottom, marginTop]);
const color = d3.scaleOrdinal()
.domain(series.map(d => d.key))
.range(d3.schemeSpectral[series.length])
.unknown("#ccc");
const formatValue = x => isNaN(x) ? "N/A" : x.toLocaleString("en")
const svg = d3.create("svg")
.attr("width", width)
.attr("height", height)
.attr("viewBox", [0, 0, width, height])
.attr("style", "max-width: 100%; height: auto;");
svg.append("g")
.selectAll()
.data(series)
.join("g")
.attr("fill", d => color(d.key))
.selectAll("rect")
.data(D => D.map(d => (d.key = D.key, d)))
.join("rect")
.attr("x", d => x(d.data[0]))
.attr("y", d => y(d[1]))
.attr("height", d => y(d[0]) - y(d[1]))
.attr("width", x.bandwidth())
.append("title")
.text(d => `${d.data[0]} ${d.key}\n${formatValue(d.data[1].get(d.key).population)}`);
svg.append("g")
.attr("transform", `translate(0,${height - marginBottom})`)
.call(d3.axisBottom(x).tickSizeOuter(0))
.call(g => g.selectAll(".domain").remove());
svg.append("g")
.attr("transform", `translate(${marginLeft},0)`)
.call(d3.axisLeft(y).ticks(null, "s"))
.call(g => g.selectAll(".domain").remove());
return Object.assign(svg.node(), {scales: {color}});
}