This chart visualizes the number of smallpox death cases each year between 1950 and 1970. A green area under a solid black line, rendered as SVG, shows the trend over time. The visualization uses D3 v5 to load and parse CSV data, apply linear scales for both axes, and generate the smoothed line and area paths using `line()`, `area()`, and `curveBasis()`. Axis components are built with `axisBottom()` and `axisLeft()`.