A four-state back-to-back band chart — two cohorts mirrored on one shared scale, with per-side totals, an earlier period overlaid as dashed outlines, and every band keyboard-reachable with a readout.
npx shadcn@latest add @zyeon/chart-pyramidZyeon UI limits how often it can be asked, and Population Pyramid hasn't had its turn. Its source will show here once it has.