This grouped bar chart displays the unsheltered homeless population in New York from 2009 to 2012, broken down by borough, surface total, subway, and overall total. It uses a nested band scale (`d3.scaleBand` twice) with an ordinal color scale to distinguish years alongside a linear y-scale for population counts. Rendered as SVG via the d3.v5 library, the chart includes axes, a legend, and a title, all styled with CSS. The data originates from a small CSV file embedded directly in the JavaScript code.