Process data curves are plots of process characteristics as a function of time over one cycle. Statistical analysis of these curves has not been feasible in the past due to lengthy calculations compounded by large data sets. This paper presents a statistical analysis method for process data curves using today's computers.This method involves collection of process data, descrete models creation, and the calculation of control limit curves. When plotting process data with control limit curves, variation can be identified and improvements can be made to the process. This technique of statistical process control can be applied to numerous process.