trading symbols AC (Open Auction) and ZE (Electronic). Metals Precious metals Precious metals currently traded on the commodity market include gold, platinum, palladium and silver which are sold by the troy ounce. One of the main exchanges for these precious metals is COMEX. According to the World Gold Council, investments in gold are the primary driver of industry growth. Gold prices are highly volatile, driven by large flows of speculative money. Industrial metals Industrial metals are sold by the metric ton through the London Metal Exchange and New York Mercantile Exchange. The London Metal Exchange trades include copper, aluminium, lead, tin, aluminium alloy, nickel, cobalt and molybdenum. In 2007, steel began trading on the London Metal Exchange. Iron ore has been the latest addition to industrial metal derivatives. Deutsche Bank first began offering iron ore swaps in 2008, other banks quickly followed. Since then the size of the market has more than doubled each year between 2008 and 2012. Agriculture Agricultural commodities include grains, food and fiber as well as livestock and meat, various regulatory bodies define agricultural products. In 1900, corn acreage was double that of wheat in the United States. But from the 1930s through the 1970s soybean acreage surpassed corn. Early in the 1970s grain and soybean prices, which had been relatively stable, "soared to levels that were unimaginable at the time". There were a number of factors affecting prices including the "surge in crude oil prices caused by the Arab Oil Embargo in October 1973 (U.S. inflation reached 11% in 1975)". On 21 July 2010, United States Congress passed the Dodd–Frank Wall Street Reform and Consumer Protection Act with changes to the definition of agricultural commodity. The operational definition used by Dodd-Frank includes "[a]ll other commodities that are, or once were, or are derived from, living organisms, including plant, animal and aquatic life, which are generally fungible, within their respective classes, and are used primarily for human food, shelter, animal feed, or natural fiber". Three other categories were explained and listed. In February 2013, Cornell Law School included lumber, soybeans, oilseeds, livestock (live cattle and hogs), dairy products. Agricultural commodities can include lumber (timber and forests), grains excluding stored grain (wheat, oats, barley, rye, grain sorghum, cotton, flax, forage, tame hay, native grass), vegetables (potatoes, tomatoes, sweet corn, dry beans, dry peas, freezing and canning peas), fruit (citrus such as oranges, apples, grapes) corn, tobacco, rice,