The investment seeks to provide investment results that, before expenses, generally correspond to the price and yield performance of the S&P MidCap 400 Index. The Trust holds the Portfolio and cash and is not actively "managed" by traditional methods. To maintain the correspondence between the composition and weightings of Portfolio Securities and component stocks of the S&P MidCap 400 Index, the Trustee adjusts the Portfolio from time to time to conform to periodic changes in the identity and/or relative weightings of Index Securities.