According to CoinMeta, analyst Willy Woo cited a Bitcoin custody report by River which stated that over the past 16 years, more than 3 million BTC coins were lost due to custody issues. Of these, approximately 1.57 million coins are presumed to be permanently inaccessible, and another 1.51 million coins were lost due to events such as hacker attacks on exchanges, internal thefts, and bankruptcies. The report indicates that about 98% of the incidents involving the permanent loss of Bitcoin occurred before 2020.