This example shows monthly Sales, Profit, and Expenses for a company from 2013 to 2015, combining translucent blue bars for sales with colored lines for each metric. The visualization uses D3 v7 to load CSV data, with `d3.scaleBand` and `d3.scaleLinear` for axes, `d3.line` for the line paths, and `d3.axisBottom` and `d3.axisLeft` for ticks. A hover tooltip and a color-coded legend support interpretation of the multi-series data.