1. Once an employee has enrolled in a retirement plan, contributions (if defined for a plan) are cumulated in payroll, in addition to hours and earnings.
2. When payroll data is required for service calculation and you are certain that it is not subject to retrocalculation, you extract it to the Retirement Plan Cumulations infotype (0602). Service calculation can take place in preparation for data transfer to the TPA.
3. When you are sure that you have extracted a complete and up-to-date set of cumulation data, you run service calculation.

For calculation using the elapsed time method, data is read from infotypes that directly or indirectly provide information about employment period. For calculation using the hours-counting method, hours data is read from the extracted payroll results.

The calculation results are written to the Retirement Plan Valuation Results infotype (0565).

4. When data is required by the TPA for the calculation of projected retirement benefits, you generate two IDocs; one containing plan participation data and the other containing service calculated in the SAP System and other data required for calculating projected retirement benefits. You make these IDocs available to the TPA.

You must ensure that the IDocs contain data for an identical period in time and generate them in close succession to avoid discrepancies due to changes in data.

5. When the TPA returns the results of benefit calculation, you trigger inbound IDoc processing in order to transfer data to your SAP System.

Projected retirement benefits and service data are stored in your system. If you want to enable employees to display their most recently calculated service and benefits, you can implement the Employee Self-Service Retirement Benefits.