The Trust seeks to achieve its investment objective by holding a portfolio of the common stocks that are included in the Index (the Portfolio), with the weight of each stock in the Portfolio substantially corresponding to the weight of such stock in the Index. In this prospectus, the term Portfolio Securities refers to the common stocks that are actually held by the Trust and make up the Trusts Portfolio, while the term Index Securities refers to the common stocks that are included in the Index, as determined by the index provider, S&P Dow Jones Indices LLC (S&P). At any time, the Portfolio will consist of as many of the Index Securities as is practicable. To maintain the correspondence between the composition and weightings of Portfolio Securities and Index Securities, State Street Global Advisors Trust Company (the Trustee), or its parent company, State Street Bank and Trust Company (SSBT), adjusts the Portfolio from time to time to conform to periodic changes made by S&P to the identity and/or relative weightings of Index Securities in the Index. The Trustee or SSBT aggregates certain of these adjustments and makes changes to the Portfolio at least monthly, or more frequently in the case of significant changes to the Index.