This interactive visualization displays regional population data over time, where each region appears as a color-coded circle whose radius corresponds to a selected year’s population value. A slider controls the year from 1946 onward, triggering a smooth transition that resizes the circles to reflect changing data. The SVG renderer uses D3.js v3 scales and axes, with circle positions fixed by an ordinal x-axis and a linear y-scale for sizing. Hovering reveals tooltips with region and population details, while the data is loaded from an external CSV file.