1. A method for managing a collateralized obligation to satisfy investment ratings requirements, comprising the steps of: determining at least one combination of quality data associated with collateral to satisfy requirements for a preselected investment ratings category for a collateralized obligation including said collateral, said at least one combination of collateral quality data forming a basis for a matrix of collateral quality data; expanding said matrix to a size mathematically suitable for performing a correlation/regression analysis on said collateral quality data; performing a correlation/regression analysis on said collateral quality data to generate a mathematical relationship that best fits said data; and using said mathematical relationship in lieu of said matrix to guide at least one of purchases and sales of said collateral such that said collateralized obligation satisfies said requirements for said preselected investment ratings category.