How to read this: each growth figure is the 12-month change in that function's headcount, weighted by team size across every reporting company on that side of the index (source: PDL v25 — snapshot frozen as of the July 2026 harvest; role-level data refreshes only on calibration re-harvests). Weighting by headcount keeps one tiny team's +300% from distorting a function's story. Sorted by the AI-native vs legacy gap — the wider the gap, the harder the transition is redrawing that function.