Various studies, such as by Irwin and Saunders (2010) and Gilbert (2009) provide differing conclusions as to whether index funds have caused the 2006-08 bubble in commodity prices. Price volatility refers to unpredictable price movement. The nature of volatility, in terms of periodicity of movements, either daily, monthly, yearly, or season of a year may have differing implications for producers or consumers depending on the commodity.3 Agricultural prices have followed a long run stagnant trend, punctuated by high spikes, at least one study has identified three major spikes over the period 1970 to 2008.4 In terms of causes, volatility fundamentally follows from the dependence of agricultural production on weather conditions, which can have direct impacts on the variability of yields.