Olmstead (2013) suggests that “while water prices, on the whole, do not seem to be higher in more arid regions, water marketing is more prevalent in arid regions. In a Coasian sense, the mere existence of the potential gains from trading water creates pressure for trade to occur, so long as the property rights are clearly assigned.” In Chile, Australia and the Western US, water trading has evolved in direct response to scarcity (Olmstead 2013). The National Water Code established in Chile in 1981 separated water rights from land rights and allowed the water rights to be traded. The response has been significant in the north-Central region (Bauer 2004). In Australia, water trading was introduced over the course of three decades, beginning in 1983 with South Australia.