A period based capacity tool which provides functionality to spread and level MS Level 1 supply proposals in periods when running at or close to the maximum capacity. Periods are user defined and are entered either in a weekly or daily manner for future periods outside the master scheduled part's planning time fence. If the defined capacity for the period exceeds, the remaining quantity will be moved to the previous period, and the spread and leveling will stop at the planning time fence which is the lower boundary. The order gap time, multiple lot size and safety lead time will not be taken into consideration if rate by period records exist.