Standard product cost could now be computed. The bill of materials and routing sheets supplied information on standard material quantities and processing time. The cost standard for material pieces and manufacturing cost rates at each cost center could then be applied to obtain standard product costs for all product code-parts, sub-assembly groups, and finished products-based on standard performance and standard rates. These frozen standard were used for profit planning and for inventory valuation. Updated for change in the bills of material, input prices, or change in processing routes and times, they could be used for current manufacturing cost control. That is costs would be authorized based on production work orders.