Even though there are only 2.2 million bitcoins available for mining, it will take 120 years or more to mine 2.2 million coins. This is because the number of bitcoins that can be mined halves every four years.
According to Chainalysis, about 20% of bitcoins cannot be used because they are lost or stuck in wallets. This is because people have lost the crypto key which is the only way to access bitcoin
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