On September 25th, there was a question from cryptocurrency analysts about the recent Coin.Dance data showing that bitcoin computing power has plummeted by more than 40% for a short period of time. Summa founder James Prestwich said that this calculation is not a real situation. This is only the case where the block interval length is over-represented in periodic sampling. This is because the time interval is too long. In addition, the probability of a block time of 18 minutes and 2 minutes may be approximately the same. However, this has a 9-fold greater impact on time-based sampling. Senior market analyst Mati Greenspan agrees with Prestwich and says he is not familiar with how computing power works. And expressed the hope that people with background knowledge can explain this. In addition, well-known derivatives trader Tone Vayes said that Bitcoin's computing power has certainly not dropped by 30%, which is more likely to be a problem with the report.