Iterative Processing of Cycles 
Use
You can process a cycle iteratively or non-iteratively.
Non-Iterative Processing
If no cyclical links exist between your cost centers, you can deselect Iterative in the cycle definition header. In this case, the SAP System processes the segments in the cycle in succession without iteration. This makes processing much faster. However, this does not correspond to hierarchy processing , because the second segment does not take the results of the first segment into account.
Note
If you want to process the cycle segments in a hierarchy, you need to create more than one cycle, and start these cycles one after the other. You can also start them all together.
You can also use the non-iterative method if the costs for internal consumption of services are to remain on the sender cost center, for example, the costs of internal energy consumption on the Energy cost center.
Iterative Processing
If you want to execute the processing iteratively, you must select "Iterative" for the cycle. The SAP System also includes cyclical relationships in the cost center network (a receiver can also be a sender of costs).
Example
Cost center A allocates (according to fixed percentage rates) to cost centers B and C. Cost center C allocates(also according to fixed percentage rates) to cost centers A and B. The allocations from cost centers A are marked with the figure 1, allocations from cost center C with the figure 2. Firstly, you carry out an allocation for cost center A, then an allocation for cost center C. This ensures that when you allocate for cost center C, the system considers the amount received from cost center A. The costs in cost center A are then allocated, where the interim amount received from C is taken into account. In this way ,the iteration is carried out until all participating sender cost centers are completely credited (unless a percentage is allocated to remain with the senders). Processing occurs hierarchically between the cycles (that is, building on one another).
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