Purpose
The network costing is used to determine, automatically, the planned costs for the activities and operating resources entered in network activities, activity elements, and components.
Prerequisites
The costing variant must be defined in the Project System IMG and stored in the network header control data. In the IMG; you can define the planned costing variant as a default value in the network type parameters.
For overhead calculation purposes, you must define a costing sheet in the activity.
Process Flow
The graphic illustrates how the system determines network planned costs:

First, the system creates a quantity structure. The quantity structure is the basis for the costing. It contains all the network data needed for the calculation.
The system valuates this quantity structure using a
costing variant. Costing variants contain the criteria for the costing and comprises:Result
You now have planned costs and overheads. The planned overhead is calculated automatically as part of costing. Depending on the network type in question, the planned costs are recorded in the network header or activity.

Depending on the costing sheet, the planned overheads are calculated using either overheads or process cost accounting.
If errors occur in the costing, the system directs your attention to the error log.
See
Calling Up the Cost Determination Error Log .
The system does not recalculate the plan costs for activities with final confirmation in activity-assigned networks. However, the procedure is different for header assigned networks. Here, the system determines the planned costs again for activities with final confirmations. If it did not, it would not be possible to correctly determine the costs in header-assigned networks.