IPD Futures Contracts are traded on the IPD UK Annual Total Return Index. Contracts traded during the year are priced using the standard Capital Asset Pricing Model (CAPM) and incorporate pricing on the basis of the capital and income performance for the year-to-date, plus the uncertainty as to the performance of property for the remainder of the year. The IPD Monthly Index provides an estimate of the current year-to-date performance. This paper outlines a simulation technique for Property Portfolio Fund Managers, Risk Managers and Multi Asset Managers to progressively (on a month by month basis) factor into their estimate the tracking error between the IPD Monthly and IPD Annual Index.