bars = {
const svg = d3.select(DOM.svg(width, height));
svg
.append("g")
.selectAll("g")
.data(aggregate)
.join("g")
.attr("transform", d => `translate(${xScale(d["year"])},0)`)
.selectAll("rect")
.data(d => keys.map(key => ({ key, value: d[key] })))
.join('rect')
.attr("x", d => x1(d.key))
.attr("y", d => yScale(d.value))
.attr("width", x1.bandwidth())
.attr("height", d => yScale(0) - yScale(d.value))
.attr("fill", d => color(d.key));
svg
.append('g')
.attr('class', 'x-axis')
.attr('transform', `translate(0,${height - margin.bottom})`)
.call(xAxis)
.selectAll("text")
.attr("x", 9)
.attr("dy", ".35em")
.attr("transform", "rotate(90)")
.style("text-anchor", "start");
svg
.append('g')
.attr('class', 'y-axis')
.attr('transform', `translate(${margin.left},0)`)
.call(yAxis);
return svg.node();
}