Sizing productivity is vital to converting department health. Too much capacity will cause costly problems. Too little capacity will cause even more costly problems. This paper will begin with simple time cycle predictions. Then we will show how to measure productivity elements required for predictions, such as run time, set change, master roll change, maintenance and upsets. Knowing how time is proportionally spent enables good decision making on productivity improvement options. Finally, we will add stochastic elements to account for irregular events, the effect of buffer (WIP) size and scheduling.