This stacked bar chart visualizes causes of death in 2013 across selected South African countries, using data from the WHO. Users can toggle between raw counts and percentage shares via radio buttons, which triggers a smooth transition in bar heights. The visualization is built with the D3.js library, specifically using `d3.layout.stack` to compute the stacked segments and `d3.svg.axis` for the axes. The chart is rendered as an SVG, and the animation is achieved through D3's `.transition()` method.