This bubble chart shows the correlation between country populations in 2000, 2010, and 2020, with the x-axis, y-axis, and bubble size each representing one of those years. The code uses d3.csv to load population data, d3.scaleLinear for axes and bubble sizing, and d3.scaleOrdinal with d3.interpolateTurbo for coloring by country. Animated hover interactions reveal tooltips showing the country name, while a legend explains the 2020 population scale.