Pie charts are delicious, but we shouldn't serve them with every meal
As you noted, the number of segments may need to be recalculated. The segmented donut from the Education Development Trust has a fatal flaw: The the chart doesn't show the data. It shows 22 of 24 segments in orange. 22/24 is 91.67%, not 96%. If they wanted to round the numbers to only show complete segments they should have used 23 of 24 segments. That would have been 95.83% Better would have been to show 23 and a little sliver to show the remaining 0.04.