According to a method of simulation data processing, a difference is determined between a simulated value of a characteristic for a simulated integrated circuit device and a corresponding empirical value of the characteristic for a fabricated integrated circuit device. A data structure containing a simulation model of the fabricated integrated circuit device is accessed, where the data structure includes a plurality of entries each accessed via a unique index and an index used to access the data structure is offset in accordance with the difference between the simulated value and the empirical value. Operation of the simulated integrated circuit device is then simulated utilizing a value obtained from one of the plurality of entries of the data structure. Results of the simulation are stored in a data storage medium.