币界网报道:The Altcoin Season Index has dropped 21%, signaling a strong Bitcoin season as BTC dominance rises. Data shows altcoins underperforming against Bitcoin over the past 90 days, with only 25% of top 50 altcoins outperforming BTC compared to 75% during typical altcoin seasons. Analysts note this shift indicates capital is rotating from altcoins back to Bitcoin, potentially due to macroeconomic uncertainty and anticipation of Bitcoin ETF approvals. The index measures altcoin performance relative to Bitcoin, with readings below 25 considered "Bitcoin season" territory. Market observers suggest this trend may continue until clearer regulatory frameworks emerge or new narratives revive altcoin interest.