This area chart displays US population in millions over time, using a smooth curve to emphasize trends and an aqua-filled region beneath the line to highlight magnitude. The visualization is built with D3 v5, importing `scaleTime`, `scaleLinear`, `line`, `area`, and `curveBasis` to generate the SVG paths. Data is loaded from a CSV file hosted on GitHub, parsed with `csv`, and rendered with custom axes, tick marks, and labels. The chart uses a time-based x-axis and linear y-axis, with population values formatted using `format`.