The X-bar chart is a control chart which tracks the mean or the average of sub-groups of up to 6 different data points.  Although the charts are not as sensitive as the I and MR charts they are very effective and easy to use when looking analyse whether a process is under control or not. The X-bar chart typically is used when monitoring characteristics that can be measured on a continuous basis. 

  The R-Bar chart is another control chart which is used to monitor control of a "range".  The R-Bar control chart tracks the difference between the maximum and minimum values in a subgroup. 

​  An inventory policy outlines the organization's vision, objectives and goals with regards to inventory.  It will also define how the company intends to manage its inventory at all levels of the organization.

  The Sales and Operations or S&OP processes mission is to balance supply and demand at an aggregate level, to align operational planning with financial planning, and to link strategic planning with tactical/operational planning.  It does this through a series of meetings which are designed to guide a group of individuals towards consensus of "ONE" plan.