This visualization shows supermarket sales over years as a smooth area chart, with the area beneath the curve filled to emphasize sales volume trends. It uses D3 v5’s `scaleLinear` for both axes, `area()` and `line()` generators with `curveBasis` for smoothing, and `axisBottom`/`axisLeft` for labeled axes. The chart renders as an SVG in a React framework, loading data from a CSV fetched via `csv()`, with tick formatting applied via `format('.3s')`.