This visualization uses a packed bubble chart to display the frequency of values across years, with each bubble sized and colored according to its numeric value. The data comes from a CSV file listing years and corresponding counts. The code loads the data with d3.csv, processes it into a hierarchy, and applies d3.pack() to compute circle positions. Circles are rendered as SVG groups with fill colors from d3.scaleOrdinal and d3.schemeCategory20c. Text labels are clipped to each circle, and hover tooltips show the exact year and value. The layout uses a fixed width of 960 pixels with automatic height.