This treemap visualizes the distribution of hedge fund assets under management (AUM) by country, with each rectangle sized proportionally to the total AUM for that nation. The chart uses d3.hierarchy and d3.treemap to compute the layout, then renders rectangles as SVG elements with a categorical color scale via d3.scaleOrdinal. Hovering a rectangle triggers a tooltip showing the country name and its aggregated AUM value, which the code sums from the CSV data source. The visualization is fully responsive, recalculating dimensions on window resize.