1. A computer program product comprising a computer readable storage medium having readable program code embodied in the storage medium, the computer program product includes at least one component operable to: create a correlation between a process and a process parameter of an integrated circuit; use capabilities of statistical timing to model the correlated process and process parameter, wherein the capabilities of statistical timing used to model the correlated process and process include at least one correlation coefficient; use the at least one correlation coefficient to model a deterministic supply voltage adjustment according to the process parameter, wherein the at least one correlation coefficient is calculated using expected values and standard deviations for the process and the process parameter and the deterministic supply voltage adjustment is modeled based on the correlation between the process and the process parameter; collapse the process and the process parameter into a new parameter that is a linear combination of the process and the process parameter based on the at least one correlation coefficient; perform statistical static timing analysis (SSTA) such that the new parameter is propagated into the SSTA rather than the process and the process parameter separately; and use the new parameter to project slack of the integrated circuit.