In the 1940s, British economist Keynes proposed the idea of โโusing about 30 representative commodities as value anchors to issue the international currency Bancor. Other countries or institutions then use Bancor as the value anchor to issue their own currencies. Since there was no decentralized blockchain system at that time, it was difficult for this program to be actually implemented and implemented. Instead, the U.S. dollar became an international currency. After the emergence of the Ethereum system, the Bancor algorithm received strong support for technical implementation.