At the time of writing, over 80% of all existing bitcoins will already be extracted. It is estimated that bitcoin will reach its final figure in 2140. Over the years, the number of coins in circulation has been adjusted by means of a complex calibration of the rewards obtained by miners. Bitcoins are assigned to miners who solve a mathematical problem using intensive computations. The number of rewards is halved every 210,000 blocks, according to Bitcoin’s original algorithm. Immediately after the launch of Bitcoin, the miners mined 50 coins as a reward for problem solving. It was reduced to 25 in 2012 and 12.5 in 2016. In 2020, miners can expect to receive 6.25 bitcoins as a reward. It’s unclear why Satoshi created Bitcoin as they did; the person behind the identity never showed up to explain. This means that the limit of 21 million Bitcoins could be a significant number for some reason; it could be mathematically logical in a way that is not yet clear, or it could be an arbitrary figure that appeals to Satoshi for some reason. Similarly, it is unclear whether there is a reason why four-year intervals have been chosen to reduce Bitcoin rewards. However, it is possible to understand why Satoshi wanted to limit the supply of cryptocurrency. The idea is that Bitcoin behave like gold, a limited resource that requires more and more time and money and is expensive to find and get out of the ground. Like those who extract gold, those who create new bitcoins are called miners. The importance of scarcity is that central agencies, such as banks, can not manipulate the economy simply by creating more money. Some currencies, such as the US dollar, were once linked to the gold standard. In other words, the value of the currency was directly related to a specific price of gold. If the government bought gold, for example, at $500 an ounce, a dollar was worth 1/500th of gold. Countries have finally abandoned the gold standard of the fiat currency, so named because its value is controlled by the decree, rather than the value of a rare product. For example, a central bank can influence the economy by printing more money, using it to buy bonds and injecting more money into the system. This is a process known as quantitative easing. Some economists would like a return to the gold standard, while others argue for the flexibility offered by banknote money to bankers. The controlled offer of Bitcoin removes this option from bankers. Once the operation is completed, 21 million Bitcoins will no longer be in circulation. Many bitcoins are lost or destroyed, accidentally or deliberately. People who lose their private keys – or even their computers – for example. They exist because they have been extracted, but they are very unlikely to be active on the market. The number of new mined bitcoins decreasing, the price should increase further, because of the basic supply and the free market mechanism. However, bitcoins can be divided by eight decimal places, each representing one hundredth of a single bitcoin, called Satoshi. In total, there will be 2.1 quadrillions of Satoshis, which is more than enough for everyone on the planet to have a share, if the cryptocurrency were to reach that point.