S&P 500 index, daily close (FRED series SP500), Federal Reserve Bank of St. Louis, https://fred.stlouisfed.org/series/SP500, period 2016-09-26 to 2026-09-25, downloaded 27 Sep 2026. Brent crude oil, Europe, daily spot price in USD (FRED series DCOILBRENTEU), Federal Reserve Bank of St. Louis, https://fred.stlouisfed.org/series/DCOILBRENTEU, period 2016-09-26 to 2026-09-25, downloaded 27 Sep 2026. USD/EUR exchange rate, daily (FRED series DEXUSEU), Federal Reserve Bank of St. Louis, https://fred.stlouisfed.org/series/DEXUSEU, period 2016-09-26 to 2026-09-25, downloaded 27 Sep 2026.