Editing Commodity market (section)

===Futures contract===
[[Futures contract|Futures]] contracts are standardized forward contracts that are transacted through an exchange. In futures contracts the buyer and the seller stipulate product, grade, quantity and location and leaving price as the only variable.<ref>Garner, Carley. ''A Trader's First Book on Commodities''. (New Jersey: FT Press, 2010): pg 19.</ref>

Agricultural futures contracts are the oldest, in use in the United States for more than 170 years.<ref>[[Futures Trading Act of 1921]], Declared unconstitutional in [[Hill v. Wallace]] 259 U.S. 44 (1922), the [[Grain Futures Act]] of 1922 and ''[[Board of Trade of City of Chicago v. Olsen]]'' 262 U.S. 1 (1923).</ref> Modern futures agreements, began in Chicago in the 1840s, with the appearance of [[grain elevators]].<ref>Cronon, William. ''Pricing the Future: Grain''. Nature's Metropolis: Chicago and the Great West. University of Chicago, 1991. pp.109-133</ref> Chicago, centrally located, emerged as the hub between Midwestern farmers and east coast consumer population centers.