CoinMarketCap's Altcoin Season Index has recorded a score of 23, indicating a market phase dominated by Bitcoin. This index, which measures the 90-day performance of the top 100 cryptocurrencies against Bitcoin, suggests that only 23% of these assets have outperformed Bitcoin, highlighting its market leadership. A score below 25 typically signifies a 'Bitcoin season,' where Bitcoin outshines most altcoins. The index's calculation excludes stablecoins and wrapped tokens, focusing on genuine performance comparisons. Historically, a score of 75 or higher marks an 'altcoin season,' last seen in early 2021. The current low reading reflects a period where Bitcoin's dominance is reinforced by factors such as regulatory clarity and the influx of capital through Bitcoin spot ETFs. Investors are advised to monitor for potential shifts that could signal a transition to an altcoin-favorable market.