D3 Barchart
This example displays a horizontal bar chart of the ten most populous countries, with population values derived from a CSV file and scaled by 1000. The chart uses D3 v5’s `scaleLinear`, `scaleBand`, `axisLeft`, and `axisBottom` to position bars and axes. Population ticks are formatted with `format('.3s')` and converted from millions to billions. The SVG is rendered in a React context, with bars styled using steelblue fills and axes annotated with a population label and title.