Bitcoin has surged to $81,000, but derivatives markets are flashing an unusual signal: the longest streak of negative funding rates this decade. The leading crypto is up 2.9% over the past 24 hours and is currently hovering at around $81,250, according to CoinGecko. The 30-day average funding rate for Bitcoin perpetual swaps—contracts that track Bitcoin's spot price without an expiry date—has remained negative for 66 consecutive days, according to a Monday tweet from Vetle Lund, head of research at K33 R ...