There is an interesting phenomenon in Bitcoin mining called the “halving paradox.” During the ten years of Bitcoin's existence, 18 million coins were mined, but it will take another 120 years to mine the remaining 3 million (a total of 21 million BTC, as Satoshi Nakamoto decided).
The reason for this is simple: halving is the process of reducing the reward for each mined block.
Let's look at a current example: Today, miners receive 12.5 BTC for each block mined. After the halving, this reward will decrease to 6.25 BTC, which will double the time it takes to generate Bitcoin in 10 minutes.
A total of 64 halvings are planned, which occur every 210,000 blocks. Two halvings have already occurred (in November 2012 - the reward decreased from 50 BTC to 25 BTC, and in June 2016 - the reward decreased from 25 BTC to 12.5 BTC), and each time the number of coins mined over a certain period of time decreases . This is why Bitcoin mining has increased so quickly to date and will continue to do so for so long into the future.
Simply put, the reward was initially 50 BTC per block. We multiply this amount by the number of blocks (210,000) and we get 10.5 million BTC. This number of coins was mined before the 2012 halving. The reward then decreased to 25 BTC, and the next 210,000 blocks yielded 5.25 million BTC. Thus, 15.75 million BTC have already been mined. And so on down the slope!
