One of the biggest factors to differentiate Bitcoin and fiat currency is the total supply of 21 million. The downfall of the various crypto exchanges over the last decade has permanently taken out at least 1.2 million BTC (5.7%) of the total issuable Bitcoin from circulation. Over 14 crypto exchanges are responsible for the loss of 1,195,000 BTC (6.3%) of the 19.2 Bitcoin currently in circulation.