Historical trend of BTC market capitalization ratio**

- **2015-2017**: The dominance of BTC has long been maintained at over 80%, especially during the bull market in 2017, when market attention was focused on Bitcoin, with its share exceeding 85% at one point.
- **2018-2020**：With the rise of the Ethereum ecosystem and the explosion of DeFi (decentralized finance) projects, the BTCMarket Cap ratio gradually decreased, reaching a low of about 40%-50% in 2020.
- **2021-2023**：BTC rebounds driven by institutional investors, with its market share rising to 50%-60%. In 2024, influenced by factors such as the approval of spot ETFs, its share stabilizes at around 57.7%.
- **2024-2025**: According to forecasts, if the BTC dominance drops below 40%, it may signal a market shift to a high-risk period of altcoin speculation.

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### **2. Key Data Points (Example)**
| Year | BTC Market Cap Share (Estimated) | Note |
|------------|------------------------|------------------------------|
| **2015** | 80%-85% | The market is dominated by BTC |
| **2017** | Over 85% | Reached peak during bull market |
| **2020** | 40%-50% | The rise of DeFi and altcoins |
| **2023** | 50%-55% | Institutional funds flow back to BTC |
| **2024** | 57.7% | Stable after spot ETF approval|
| **2025 Prediction** | May be less than 40% | If the market shifts to the altcoin cycle |

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### **3. Chart Design Recommendations**
- **Timeline**: The horizontal axis represents the years (2015-2025), and the vertical axis represents the percentage (0%-100%).
- **Key Annotation**:
- Peak of the bull market in 2017 (more than 85%);
- The low point caused by the DeFi outbreak in 2020 (40%-50%);
- Stabilization period after the ETF in 2024 (57.7%);
- Potential altcoin cycle in 2025 (forecast below 40%).
- **Data Source Annotation**: Historical data from platforms such as CoinMarketCap, Coinglass, etc. can be referenced.

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