Bitcoin experienced a significant downturn in Q4 2025, with ETF outflows accelerating and the cryptocurrency's price falling 23% from the start of Q3. ETF assets under management decreased from $163 billion in October to $116 billion, marking the weakest quarter since the FTX collapse. This trend highlights a growing correlation between Bitcoin ETF flows and S&P 500 movements, as institutional investors increasingly apply stock-like strategies to crypto investments. Analysts suggest a potential liquidity shift to cryptocurrencies in 2026 if market conditions improve.