This example visualizes average sales amounts by sales channel, with a bar chart comparing categories from an Amazon Sale Report dataset loaded via `d3.csv`. The code computes group means using `d3.rollups` and `d3.mean`, then renders the bars with SVG rectangles. It uses `d3.scaleBand` for the x-axis, `d3.scaleLinear` for the y-axis, and includes rotated axis labels and a title. Data is fetched from a GitHub raw URL, and the chart is built with D3 v7 within an 800x400 pixel container.