This example presents an average monthly sales bar chart, displaying sales data from a CSV file across repeated calendar years. The visualization aggregates repeated monthly entries into bars, showing the overall sales distribution for each month. Built with D3 v7, the code loads data via `d3.csv`, maps sales values to numbers, and constructs the chart using `d3.scaleBand` for the x-axis and `d3.scaleLinear` for the y-axis. SVG rectangles represent each bar, while `d3.axisBottom` and `d3.axisLeft` render the axes, with a title added as an SVG text element.