Computers and data processing systems, especially pertaining to a constant-dollar financial product. Exemplary implementations include, a machine, a method for use and method for making, and corresponding products produced thereby, as well as data structures, computer-readable media tangibly embodying program instructions, manufactures, and necessary intermediates of the foregoing. Respectively, computers can use private, constant-dollar financial product data and nominal dollar data corresponding thereto, and communicate so as to cooperate (e.g., including transmit, receive) in computing a constant dollar to nominal dollar conversion for a financial product, the computers generating different output.