1. A data processing system for calculating a distribution of a quantity over a plurality of receiver objects, the data processing system comprising: a plurality of application programs adapted to generate a distribution request; a storage means for storing: a plurality of rules adapted for distribution of at least a portion of the quantity over the receiver objects; and assignments of sub-sets of the plurality of rules to the application programs, the rules of the assigned sub-sets having: identifiers associating the rules of the assigned sub-sets with an application program; assigned priorities of execution; and distribution calculation means for: receiving a distribution request from one of the application programs, the received distribution request comprising: the identifier of the sub-set of rules assigned to the one of the application programs, the quantity to be distributed, and identifiers of receiver objects over which the quantity is to be distributed, the distribution calculation means being adapted to access the storage means in order to execute the sub-set of rules assigned to the one of the application programs, the execution in the order of the priorities assigned to the rules within the sub-set of rules assigned to the one of the application programs; and where the rules are parameterizable; wherein at least a sub-set of the parameters of one of the rules is assigned parameter values when the assignment of the sub-set of rules to an application program is stored.