The full daily history of the US stock Fear & Greed index from 2016 to today, each point a date and 0–100 score. Pass `?days=N` to return only the most recent N days (default: full series). Use for charting sentiment regimes and backtesting against price. Companion to /api/v1/fear-greed (current reading). From x402stock, a market & economic data API (x402, USDC).