system of national fiat monies has been used globally, with variable exchange rates between the major currencies. Precious metal coinage During the 1960s, production of silver coins for circulation ceased when the face value of the coin was less than the cost of the precious metal it contained (whereas it had been greater historically). In the United States, the Coinage Act of 1965 eliminated silver from circulating dimes and quarter dollars, and most other countries did the same with their coins. The Canadian penny, which was mostly copper until 1996, was removed from circulation altogether during the autumn of 2012 due to the cost of production relative to face value. In 2007, the Royal Canadian Mint produced a million dollar gold bullion coin and sold five of them. In 2015, the gold in the coins was worth more than 3.5 times the face value. Money creation and regulation A central bank introduces new money into an economy by purchasing financial assets or lending money to financial institutions. Commercial banks then redeploy or repurpose this base money by credit creation through fractional reserve banking, which expands the total supply of "broad money" (cash plus demand deposits). In modern economies, relatively little of the supply of broad money is physical currency. For example, in December 2010 in the U.S., of the $8,853.4 billion of broad money supply (M2), only $915.7 billion (about 10%) consisted of physical coins and paper money. The manufacturing of new physical money is usually the responsibility of the national bank, or sometimes, the government's treasury. The Bank for International Settlements published a detailed review of payment system developments in the Group of Ten (G10) countries in 1985, in the first of a series that has become known as "red books". Currently the red books cover the participating countries on Committee on Payments and Market Infrastructures (CPMI). A red book summary of the value of banknotes and coins in circulation is shown in the table below where the local currency is converted to US dollars using the end of the year rates. The value of this physical currency as a percentage of GDP ranges from a maximum of 19.4% in Japan to a minimum of 1.7% in Sweden with the overall average for all countries in the table being 8.9% (7.9% for the US). The most notable currency not included in this table is the Chinese yuan, for which