This example shows three different ways to visualize the same percentage: the current day of the year as a fraction of the total days in the year, computed using `timeFormat` from d3. It presents a progress bar, a donut chart, and a semicircular gauge side by side, each displaying the computed value. The React components render SVG primitives, with the donut and gauge using d3’s `arc` generator to create their shapes. The progress bar uses simple SVG rectangles, and all three update dynamically based on the current date.