This stacked horizontal bar chart displays population distribution across multiple countries for the years 1950–2020, with each bar segment representing a yearly population count. It uses d3.csv to load the data, d3.stack() to compute the stacked segments, and d3.scaleOrdinal with d3.schemeCategory10 for color encoding. Hovering over a segment highlights it and shows a tooltip with the specific year and population value, using d3.axisLeft, d3.axisBottom, and d3.scaleBand.