<P> The United States dollar (sign: $; code: USD; also abbreviated US $and referred to as the dollar, U.S. dollar, or American dollar) is the official currency of the United States and its territories per the United States Constitution since 1792 . For most practical purposes, it is divided into 100 smaller cent (¢) units, but is occasionally divided into 1000 mills (₥) for accounting purposes . The circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars (12 U.S.C. § 418). </P> <P> Since the suspension in 1971 of convertibility of paper U.S. currency into any precious metal, the U.S. dollar is, de facto, fiat money . As it is the most used in international transactions, the U.S. dollar is the world's primary reserve currency . Several countries use it as their official currency, and in many others it is the de facto currency . Besides the United States, it is also used as the sole currency in two British Overseas Territories in the Caribbean: the British Virgin Islands and Turks and Caicos Islands . A few countries use the Federal Reserve Notes for paper money, while still minting their own coins, or also accept U.S. dollar coins (such as the Sacagawea or presidential dollar). As of June 27, 2018, there are approximately $1.67 trillion in circulation, of which $1.62 trillion is in Federal Reserve notes (the remaining $50 billion is in the form of coins). </P> <P> Article I, Section 8 of the U.S. Constitution provides that the Congress has the power "To coin money". Laws implementing this power are currently codified at 31 U.S.C. § 5112 . Section 5112 prescribes the forms in which the United States dollars should be issued . These coins are both designated in Section 5112 as "legal tender" in payment of debts . The Sacagawea dollar is one example of the copper alloy dollar . The pure silver dollar is known as the American Silver Eagle . Section 5112 also provides for the minting and issuance of other coins, which have values ranging from one cent to 100 dollars . These other coins are more fully described in Coins of the United States dollar . </P> <P> The Constitution provides that "a regular Statement and Account of the Receipts and Expenditures of all public Money shall be published from time to time". That provision of the Constitution is made specific by Section 331 of Title 31 of the United States Code . The sums of money reported in the "Statements" are currently being expressed in U.S. dollars (for example, see the 2009 Financial Report of the United States Government). The U.S. dollar may therefore be described as the unit of account of the United States . </P>

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