This interactive donut chart visualizes income breakdown across three categories—Sales, Dividends, and Interest—using repeated rows from a CSV file. Built with D3 v5, it renders an SVG donut with labeled slices and a hover tooltip displaying each category’s percentage. The code leverages `d3.pie` for arc calculation, `d3.arc` for path geometry, and `d3.scaleOrdinal` for color mapping. Hovering highlights a slice and dynamically positions a tooltip using mouse coordinates.