Strategy → sub-strategy → fund. Each ring is one level of the hierarchy; each arc's angular span is its share of the parent. Best when you want to show two or three levels of decomposition without a 50-row table. Slightly more compact than a treemap for shallow hierarchies.
D3 v7's d3.partition. Edit the ROOT object — nested children with value on leaves.
const ROOT = { name: "Aqua", children: [ { name: "Private Equity", children: [ { name: "Buyout", children: [...] }, { name: "Growth", children: [...] }, ]}, // ... etc ] };
2-3 level hierarchies. More elegant than treemap for shallow, balanced trees. Avoid for very deep trees (4+ levels) — labels get cramped. Use a collapsible tree instead.
Inner ring = strategy (largest); outer rings = sub-strategy then fund. Angular span = AUM share. Hover any arc for the segment's path and value.