According to Adam Back, the prior Bitcoin halving cycle began in May 2020 and topped in March 2024 at $73.7k. Source: Adam Back on X, Aug 13, 2025. He notes earlier peaks during that cycle at $64.8k in April 2021 and $69k in November 2021. Source: Adam Back on X, Aug 13, 2025. He adds the current cycle started in April 2024, with an estimated next cycle top window in Q4 2027 to Q1 2028 and a cycle end around March 2028 based on a four-year interval from the prior top. Source: Adam Back on X, Aug 13, 2025.