Abstract: The present invention provides a computer system for managing limited counterpart transaction orders for products or services, in particular with a ceiling price, comprising: —a source of information indexing the available products or services and explanatory variables for these products or services, as well as time related counterpart information for these products or services, —an automatic classification engine adapted to gather products or services by classes of counterpart evolution, from historical counterpart data, and to attribute to each class a set of explanatory variables and an evolution behavior, —a client interface for inputting orders on given products and services defined by explanatory variable values, with a limit counterpart value, —a class allocation engine for allocating an inputted order to at least one evolution class depending on the explanatory variable values of the order, and —an indicator computation engine capable of computing a success probability indicator for an input order, co