A dual-panel visualization shows global health and economic trends from 1800 to 2014, with a scatter plot of GDP per capita against average lifespan and a line chart tracking lifespan over time. Animated transitions update both panels as a slider or keyboard controls change the year. Tooltips reveal population details, while historical annotations like the Spanish Flu appear contextually. The implementation uses d3.v6 with `scaleLog`, `scaleLinear`, data joins, and SVG transitions, processing raw country data into Maps keyed by year.