A combined line and area chart displays automobile sales trends from 2009 to 2019, with the line tracing sales values and the area beneath filled in light blue. The visualization uses D3 v5’s `scaleTime`, `scaleLinear`, `line`, and `area` generators with a `curveBasis` smoothing, rendering as SVG. Axis ticks are formatted with `d3.format`, and data is loaded from a CSV via `d3.csv` with dates parsed using `d3.timeParse`. Gridlines are drawn through negative tick sizes on both axes.