Deregulation of the Australian Wheat Export Market: What Happened to Wheat Prices?

This paper investigates whether deregulation of the Australian wheat export market induced a structural change in the price data generation process. We examine the unit root properties of Western Australian wheat prices by testing for the possibility of single and double structural breaks in the price series. Daily prices for the period 20th of May 2003 to 14th of September 2010 are used. We find that the wheat price series has a unit root with two structural breaks but neither break coincided with the time when the Wheat Export Marketing Act 2008 came into effect on 1 July 2008. We conclude that change in local market behaviour would have started prior to actual deregulation with subsequent effect on local price.