Use this tab to view and manage cost information about your project items. Project Override and Project Level Override are the cost fields which can be modified in this tab. Values in the Project Override field will override the calculation of cost on lower levels in the project product structure. Values in Project Level Override will override the Standard Level, but they will be ignored if the corresponding Project Override field has a value. Values for Standard Level and Standard Rollup are retrieved according to the hierarchy described in the topic Project Item Cost and Hours.
The cost calculation can be done by right-clicking on the header part of the Cost tab and selecting the Calculate Cost and Hours menu option.
Create
  And Maintain Project Product Structure
  Approve
  Project Product Structure
Calculate
      Project Item Rollup Cost and Hours
Update Project Material Cost from PQL