CBOE Volatility Index, daily close (FRED series VIXCLS), Federal Reserve Bank of St. Louis, https://fred.stlouisfed.org/series/VIXCLS, period 1990-01-02 to 2026-09-25, downloaded 27 Sep 2026.
CBOE Volatility Index, daily close (FRED series VIXCLS), Federal Reserve Bank of St. Louis, https://fred.stlouisfed.org/series/VIXCLS, period 1990-01-02 to 2026-09-25, downloaded 27 Sep 2026.