According to BlockBeats, data from Coinmarketcap indicates that the Altcoin Season Index is currently at 17, down from 18 the previous day. On September 20, the index had reached a high of 78. This index reveals that over the past 90 days, approximately 17 out of the top 100 cryptocurrencies by market capitalization have outperformed Bitcoin.

The CMC Altcoin Season Index is a real-time indicator used to assess whether the cryptocurrency market is experiencing a season dominated by altcoins. It is based on the performance of the top 100 altcoins relative to Bitcoin over the last 90 days.