Abstract: Computer-implemented methods of creating and maintaining stock indexes are provided. For a stock index of a particular size, a band is defined around the upper and/or lower limits of the stock index. To be added to, or dropped from, a particular stock index, the stocks must fall outside of the bands for that particular stock index size. Stock migration is controlled using a systematic stock migration process so that stocks are gradually added and deleted from an index. Stock investment style is determined in a multi-dimensional process, instead of a linear process. Furthermore, the number of stocks in the stock index need not be a fixed value, but may depend upon how many stocks meet predefined criteria at any given point in time.

Abstract: An investment company is administered by issuing one or more classes of shares that are bought from and redeemed with the company at a net asset value, issuing one or more classes of shares that are listed for trading on a securities exchange and that are bought and sold at negotiated market prices, and maintaining, in one or more computers, account data of the outstanding shares. A shareholder may acquire exchange-traded shares by requesting conversion of a designated number or dollar value of shares belonging to the one or more classes of shares that are bought from and redeemed with the company at a net asset value for a monetarily equivalent number of shares of the one or more classes of shares which are exchange-traded shares of the company. An authorized participant may purchase exchange-traded shares directly from the investment company in exchange for a basket of securities of generally equivalent monetary value.