This area chart displays the life expectancy of the USA over time, with a blue line tracing the trend and an orange filled area beneath it, using a smooth curve. The visualization loads CSV data from a GitHub gist and renders as SVG via D3 v5, employing `scaleTime`, `scaleLinear`, `csv`, `area`, and `line` generators with `curveBasis`. It includes labeled axes for year and life expectancy, gridlines via tick sizes, and formatted tick labels.