This line chart visualizes customer counts per year from 2000 to 2010, using data loaded from a CSV file. It renders an SVG path with a thick steelblue stroke via d3.line(), with d3.scaleBand positioning years along the x-axis and d3.scaleLinear mapping customer values on the y-axis. Axes are generated using d3.axisBottom and d3.axisLeft, and labels for “Year” and “customers” are added as SVG text elements.