According to a report released by Chainalysis, in the past few years, the way in which the exchange has obtained funds can be divided into three different periods: 1. At the beginning of 2011, bitcoin had just started and mining was quite noticeable. At that time, most of the funds of the exchange were directly From miners; 2. In 2012 and 2013, before the exchange was regulated, a large part of the cryptocurrency entering the exchange came from the dark web market, presumably for cash; 3. By the end of 2013, most of the trading activities were With other exchanges, this trend continues to this day. Since the beginning of 2013, more than half of all cryptocurrencies received by exchanges have come from other exchanges, and today this number is about 75%. Why does such a large percentage of transactions occur between two exchanges? Investment activity is one possible cause. Investment and trading are two of the most prominent cryptocurrency use cases today. Users often send funds from one exchange to another for a wider range of tokens, trading pairs, and investment product businesses; arbitrage is another possible reason . In the traditional fiat currency world, the market is efficient and arbitrage opportunities are rare. But cryptocurrencies are a less mature asset. Therefore, it is not uncommon for the same cryptocurrency to have large spreads on different exchanges.