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Dollar (abbreviation: USD；; И o4217Currency code: USD; ; Symbol: USD) is the legal tender of the United States, El Salvador, Panama, Ecuador, East Timor, Marshall Islands, Kiribati and Palau. Dollar banknotes in circulation are all versions of banknotes issued since 1929.
1792 appeared after the passage of the American mint act. At present, the issuance of US dollars is controlled by the Federal Reserve system. Starting from 19 13, the United States established the federal reserve system and issued federal reserve bonds. More than 99% of the banknotes in circulation are federal reserve notes.
The competent department for issuing US dollars is Congress, and the Federal Reserve Bank is responsible for the specific issuance business. After World War II, continental European countries reached an agreement with the United States to use US dollars for international payments. Since then, the dollar has been widely used as a reserve currency in countries outside the United States, and eventually became an international currency.
In 792, the US dollar formed a currency area in the 13 colony. At that time, the United States was only a country with a population of 4 million. By the end of 19, it has become the most powerful country in the world. By the time World War I broke out in 19 14, the total economic output of the United States was already greater than that of the three largest countries: Britain, Germany, France, and even the sum of them, which made the status of the US dollar increasingly prominent. During World War I, gold from European countries flowed into the United States to buy war materials. The Federal Reserve Bank of the United States used these gold as legal tender, which led to inflation. From 19 14 to 1920, the price level in the United States nearly doubled. Later, the Federal Reserve Bank of the United States decided to control inflation and tried to restore the price to its original level. Then came the period of deflation, when the price level dropped from 200 to 1920 in one year, which was the biggest deflation in American history. Although the 35 years of the gold standard system is the "golden age" for the prosperity of liberal capitalism, the fixed exchange rate system has the advantages of ensuring the safety of international trade and credit, facilitating the accounting of production costs and avoiding international investment risks. To some extent, it has promoted the development of international trade and investment. However, the strict fixed exchange rate system makes it difficult for countries to implement favorable monetary policies according to their own economic development needs, which greatly restricts economic growth. During World War II, the international monetary system became more chaotic. In order to solve this chaotic situation, 1943, US Treasury official White and British Treasury consultant Keynes designed the post-war international monetary and financial system from their own interests, and put forward two different schemes, namely "White Scheme" and "Keynes Scheme".