This bar chart visualizes average monthly sales data across multiple years, displaying sales figures for each month from January through December. The chart uses a steel blue color scheme and rotated x-axis labels to improve readability of the month names. The visualization is built with D3 v7, loading CSV data through the `d3.csv` API and rendering the bar chart as SVG elements. The code uses `d3.scaleBand` for the categorical month axis and `d3.scaleLinear` for the continuous sales values, with axes generated using `d3.axisBottom` and `d3.axisLeft`.