Commodity money as a theoretical backing for federally issued "gold certificates" to substitute for the gold. Between 1933 and 1970 (when the U.S. officially left the gold standard), one U.S. dollar was technically worth exactly 1/35 of a troy ounce (889 mg) of gold. However, actual trade in gold bullion as a precious metal within the United States was banned after 1933, with the explicit purpose of preventing the "hoarding" of private gold during an economic depression period in which maximal circulation of money was desired by influential economists. This was a fairly typical transition from commodity to representative to fiat money,
United States Commodity Funds commodity ETP in the United States that invested in Brent crude oil (ticker:BNO), although previously a Brent crude oil based commodity ETP had been launched in London. In 2010, USCF launched its first non-energy specific commodity ETP, United States Commodity Index Fund (ticker:USCI), which holds a diversified basket of commodity futures based on the SummerHaven Dynamic Commodity Index ("SDCI"). The SDCI is the first broadly diversified commodity index whose commodity weightings are not fixed, but which instead are adjusted to reflect market conditions. USCF's commodity exchange traded products are all listed on the New York Stock Exchange. Prior to the