This visualization presents a dataset of cat breeds, showing both summary statistics and a breed-by-breed comparison of average age. A scrollable bar chart displays the mean age for each breed, with breed labels rotated beneath the bars. The code loads CSV data via `d3.csv`, computes averages and summaries using `d3.mean` and `d3.rollup`, and renders the chart with D3 v7’s SVG selection and scale APIs. A dynamic SVG width accommodates the full breed list, while the summary panel reports data size, row and column counts, and overall averages.