How many times is bitcoin reduced

1.

The total number of bitcoins is 21 million

in 2009, when bitcoin was born, block reward was 50 bitcoins. Ten minutes after its birth, the first 50 bitcoins were generated, and the total amount of money at this time is 50. Then bitcoin grew at a rate of about 50 every 10 minutes. When the total amount reaches 10.5 million (50% of 21 million), the block reward will be halved to 25

when the total amount reaches 15.75 million (5.25 million new output, i.e. 50% of 1050), the block reward will be further halved to 12.5. The monetary system used to have no more than 10.5 million in four years, after which the total number will be permanently limited to about 21 million

extended data

monetary characteristics

1. Decentralization: bitcoin is the first distributed virtual currency, and the whole network is composed of users without a central bank. Decentralization is the guarantee of bitcoin's security and freedom

2. Global circulation: bitcoin can be managed on any computer connected to the Internet. No matter where you are, anyone can dig, buy, sell or collect bitcoin

3. Exclusive ownership: private key is needed to control bitcoin, which can be stored in any storage medium in isolation. No one can get it except the user himself

4. Low transaction cost: bitcoin can be remitted free of charge, but a transaction fee of about 1 bitfen will be charged for each transaction to ensure faster transaction execution

5, no hidden cost: as a means of payment from a to B, bitcoin has no cumbersome limit of quota and proceres. If you know the other party's bitcoin address, you can pay

6. Cross platform mining: users can explore the computing power of different hardware on many platforms

2. In order to understand the technical principle of bitcoin, we need to understand two important cryptographic techniques: hash code: it converts a long string into a fixed length string, and its conversion is irreversible, that is, it is impossible to guess the original string from hash code. Sha256 is mainly used in bitcoin protocol
public key system: corresponds to a public key and a private key, keeps the private key in the application and publishes the public key. When Party A transmits information to Party B, it can use Party A's private key to encrypt the information, and Party B can use Party A's public key to decrypt the information, so as to ensure that the third party cannot impersonate Party A to send the information; At the same time, when Party A transmits information to Party B, it is encrypted with Party B's public key and sent to Party B, and then Party B decrypts it with his own private key, so as to ensure that the third party cannot eavesdrop on the communication between the two people. RSA is the most common public key system, but the lliptic curve digital signature algorithm is used in bitcoin protocol. What's the difference between cash and bank account? Bitcoin is an electronic currency in BTC. In this article, it is also used to refer to the whole bitcoin system. Like opening an account in a bank, the corresponding concept in bitcoin is address. Everyone can have one or more bitcoin addresses, which are used to pay and collect money. Each address is a string that starts with 1. For example, I have two bitcoin accounts, and. A bitcoin account is uniquely determined by a pair of public key and private key. To save the account, you only need to save the private key file. Unlike bank accounts, banks keep all transaction records and maintain the book balance of each account, while bitcoin's transaction records are jointly maintained by the whole P2P network through a pre agreed protocol. How much money is in my account address? Although the current account balance can be seen by bitcoin software, unlike banks, there is no place to maintain the book balance of each address. It can only calculate the account balance in real time through all historical transactions. How do I pay? When I pay from address a to address B of the other party, the payment amount is e. at this time, both parties will announce the transaction information to each network node, telling address a to pay to address B, and the payment amount is e. In order to prevent the third party from forging the transaction information, the transaction information will be encrypted with the private key of address A. at this time, the network node receiving the transaction information can use the public key of address a to verify that the transaction information is indeed sent by address a. Of course, trading software will help us do these things, we just need to input the relevant parameters in the software. What will the network node do after receiving the transaction information? This is the most important part of the bitcoin system, which needs to be elaborated. For the sake of simplicity, only bitcoin protocol has been implemented. In the current version, each network node will save all transaction information synchronously. There are two kinds of transaction information in history, one is & quot; Verified & quot; The transaction information, that is, the verified transaction information, is stored in a series of "blocks". Each & quot; block" Is the previous & quot; bock" The ID of each block is the hash code of the hash code of the block and the new transaction information (see an actual block). The other category refers to those who also & quot; Unverified & quot; The transaction information just paid above belongs to this category. When a network node receives new unverified transaction information (possibly more than one), it can calculate the book balance of each address at that time because the node keeps all the transaction information in history, so it can calculate whether the transaction information is valid, that is, whether there is enough balance in the payment account. After eliminating the invalid transaction information, it first takes out the last & quot; block" Then, the unverified transaction information is combined with the ID, and a verification code is added to form a new "block". It needs a lot of calculation to build a new block, because it needs to calculate the verification code, so that the above combination becomes a block, that is, the first several bits of the hash code of the block are 1. At present, the first 13 bits need to be 1 (generally, the specific method is uncertain), which means that if the block is generated by enumeration method, the average number of enumerations is 16 ^ 13. Using CPU resources to generate a block is called "gold mining", because the proction of the block will get a certain reward, and the reward information has been included in the block. When a network node generates a new block, it will broadcast to other network nodes. However, this network block may not be accepted by the network, because it is possible that other network nodes have proced the block earlier. Only the earliest block or the block with the largest number of subsequent blocks is valid, and the remaining blocks are no longer used as the initial blocks of the next block. How does the other party confirm that the payment is successful? When the payment information is distributed to the network node, the network node begins to calculate whether the transaction is valid (that is, whether the account balance is enough to pay), and attempts to generate blocks containing the transaction information. When six blocks (one direct block and five subsequent blocks) contain the transaction information, the transaction information is considered "verified", so that the transaction is formally confirmed, and the other party can confirm the successful payment. A possible problem is that I will pay the balance of address a to address B, and at the same time pay to address C. If I only verify that the single comparison transaction is valid. At this point, my way of cheating is to generate six blocks including B to B and six blocks including C to C before the truth is revealed. Because I need a very long CPU time to generate a block, compared with the whole network, the probability of my cheating success is very small. What is the motivation of network nodes to proce blocks? As can be seen from the above description, in order to make the transaction information effective, the network node needs to generate 1 and 5 subsequent blocks to contain the transaction information, and such block generation is very CPU intensive. How to let other network nodes help to proce blocks as soon as possible? The answer is very simple. The agreement stipulates that BTC will be rewarded for the address where the block is proced, as well as the Commission promised by both parties. At present, the reward for procing a block is 50btc, which will be halved every four years in the future. For example, the reward will be 25btc from 2013 to 2016. Is the transaction anonymous? Yes, and No. All bitcoin transactions are visible. We can check all transaction records of each account, such as mine. But what's different from the banking monetary system is that everyone's account itself is anonymous, and everyone can open many accounts. In general, anonymity is not as good as it claims. But bitcoin has another advantage in doing black market trading: it can't be frozen. Even if the police trace a bitcoin address, there is nothing they can do unless they trace the computer used by the exchange based on the Internet address. How to ensure that bitcoin does not depreciate? Generally speaking, in the case of equivalent trading activities, the value of money is inversely proportional to the amount of money issued. Unlike the traditional money market, the central bank can determine the amount of money issued. Bitcoin does not have a central issuing institution. Only by procing blocks can we get a certain amount of BTC currency. Therefore, bitcoin's new amount of money depends on: 1. The speed of procing blocks: bitcoin's agreement stipulates that the difficulty of procing blocks is fixed at an average of 2016 every two weeks, about 10 minutes. Moore's law of doubling CPU speed every 18 months will not speed up the proction of block. 2. The number of rewards for block proction: at present, 50 BTC is awarded for each block proced, which is halved every four years. In 2013, 25 BTC is awarded, and in 2017, 12.5 BTC is awarded. Considering the above two factors, bitcoin's currency issuing speed is not controlled by any single node in the network. Its protocol makes the currency stock known in advance, and the maximum stock is only 21 million BTC

3.

Bitcoin network generates a new block every ten minutes. Every time a miner completes a block, he can get a certain amount of bitcoin as a block reward, and the reward will be halved for every 210000 blocks mined. Because the time for mining each block is limited to 10 minutes, at this rate, the period for the reward to be halved is four years, that is to say, the reward for bitcoin blocks is halved every four years

when the bitcoin block reward was halved for the first time, its price rose 25 times from 300 yuan to 7995 yuan; In the second half, the price rose 28 times from 5011 yuan to 140000 yuan. So many people predict that the third halving of bitcoin in May 2020 will lead to a sharp rise in the price of bitcoin, at least 10 times. However, these figures are not so clear. After halving in 2012, bitcoin prices rose for two months, and in 2016, there was almost no immediate response to deflation for a month. This may also be the result of the strategy of "buying rumors and selling news" implemented by some speculators

extended data:

after bitcoin halved, the supply slowed down, and keeping deflation through algorithm has always been a part of bitcoin protocol design. It was set up to ensure the value of bitcoin. By recing block incentives and setting the maximum possible supply of bitcoin at 21 million bitcoins, bitcoin has an anti inflation feature, which runs counter to the tendency of central banks to print money at will. At present, there are about 17.5 million bitcoins in circulation, and less than 3.5 million bitcoins are available for mining. When the next block award halves, bitcoin's annual inflation rate will drop from the current 3.8% to about 1.8%

maintaining deflation through algorithms has always been a part of the design of bitcoin protocol. It was created to guarantee the value of bitcoin. By recing block incentives and keeping the total amount of bitcoin at 21 million bitcoins, bitcoin is endowed with an anti inflation nature, which is different from the tendency of central banks to print money at will. At present, there are about 17.5 million bitcoins in circulation and less than 3.5 million available for mining. The next block award cut in half could rece bitcoin's annual inflation rate from the current 3.8% to about 1.8%. This will be the first time in bitcoin's history that it has fallen below the historical average of about 2% - 3% growth in gold supply

4.

2020 is the first year of digital currency proction rection. Most currencies will achieve the first proction rection this year, while bitcoin will usher in the third proction rection cycle. And the market is generally high on the halving market, it is expected that this year will usher in a wave of bull market, and the logic behind it is very clear. From the perspective of historical experience, this has already formed a more extensive "consensus" in the circle of cryptocurrency

secondly, bitcoin, known as "digital gold", is recognized by more and more funds for its risk aversion, which indirectly pushes up its price. At present, in addition to bitcoin, which has the most influence, BCH, BSV, etc, dash and other currencies are the most concerned. Dozens of counterfeit currencies have chosen to be halved in 2020. Therefore, 2020 is also known as the first year of halving

what is half bitcoin

bitcoin halving means that the reward for procing new blocks is halved about every four years. This means that after halving, the corresponding bitcoin reward for each block proced is only half of the reward before halving. At present, bitcoin has been halved twice, respectively in November 2012 and July 2016. The third half of bitcoin is expected to take place on May 13, 2020. By that time, bitcoin will be halved from 12.5 blocks to 6.25 blocks

half block reward means that it will take longer for all bitcoins to enter circulation, but it also means that mining will proce fewer and fewer new bitcoins. Moreover, e to its limited supply and increased mining difficulty, its scarcity attribute becomes more and more obvious, and scarcity will directly enhance the value. As the saying goes, scarcity is more expensive! For bitcoin, there is no doubt that this is a very big advantage

buying bitcoin in 2020 is better than buying bitcoin ETF fund

In theory, X2

3, bitcoin current price 10000x4 = US $40000 (expected price after this year's proction rection)

in this period, the return comparison between holding spot and ETF fund is as follows:

1, buying spot holding, earning three times

2, buying ETF fund, Up to 15 times (intelligent position adjustment + fund compound interest calculation)

there is no doubt that bitcoin ETF launched by bitoffer is the best investment choice