The statistical caliber of US dollar stock includes M0 (dollar cash in circulation), M 1, M2 and M3 (broad money). By the end of 2007, the US dollar cash issued by the Federal Reserve was US$ 774.3 billion. After adding current savings and traveler's checks, M 1 is US$ 0.4 million. The M2 data released in the same period is 7.5 trillion US dollars. In 2005, the United States stopped publishing the broadest monetary statistical caliber M3 (the last data released in 2005 was 10 trillion US dollars), and it is estimated that the same caliber will reach 12 trillion US dollars by the end of 2007. In addition, the European dollar deposits derived from the European money market are estimated to exceed 4 trillion US dollars according to the above method. Therefore, the total dollar currency in the global market is about 16 trillion dollars. According to the statistics of the Federal Reserve and related scholars, 60% of US dollar cash (about 450 billion US dollars) circulates outside the United States due to small personal travel, official customs transportation and underground smuggling. The currency substitution and potential liquidity risk caused by this dollar outflow are also often concerned. In addition, all dollar deposit currencies issued in the United States exist in the balance sheets of American banks. By the end of 2007, the amount of "money and deposits" under the column of "monetary authorities, banks and related financial institutions" in the United States was $654.38+$0.8 trillion, which can be approximately considered as foreign exchange deposits in dollars held by foreign governments and residents (excluding European dollars). Therefore, of the US$ 65,438+02 trillion issued by the United States, about US$ 2.25 trillion is held by overseas residents. The remarkable characteristics of American dollar stocks are: high currency multiplier and fast circulation speed. In terms of currency multiplier, the ratios of M3/M 1 and M2/M 1 in the United States are almost the highest in the world, especially since the 1960s. At the same time, the speed of money circulation in the United States is also higher than that in ordinary countries, and the proportion of generalized dollar money stock to American GDP is among the lower countries in the world. Therefore, judging from the normal speed of currency circulation, for the real economy of the United States, the US dollar has not earned over-issuance.