The total hashrate of the 13 U.S.-listed bitcoin BTC$107,661.84 miners tracked by JPMorgan (JPM) now accounts for around 31.5% of the global network, the highest level on record, the bank said in a research report on Monday.These miners added 11 exahashes per second (EH/s) of capacity since April, led by CleanSpark (CLSK), Hive Technologies (HIVE) and Riot Platforms (RIOT), the report said. The hashrate refers to the total combined computational power used to mine and process transactions on a proof-of-work blockchain, and is a proxy for competition in the industry and mining difficulty. The miners' aggregate hashrate has risen 99% year-on-year versus a 55% y/y increase in the network hashrate. The network hashrate fell about 10 EH/s to an average of 890 EH/s in the first two weeks of June, a development the bank said was "somewhat surprising." Still, it remains up over 50% year-on-year. The hash price, a measure of daily mining profitability, dropped 2% from the end of May, the report noted. The total market cap of the 13 companies rose 10%, or $2.4 billion, in the first two weeks of the month, the bank said. Riot outperformed the group with a 20% gain, while Bitfarms (BITFU) underperformed with a 9% decline, the report added. Read more: Bitcoin Miners Just Had One of Their Best Quarters on Record, JPMorgan Says