The previously saved annual salary in IT 0008 was entered manually in IT0008 (field ANSAL), the system
calculates the period salary according to rules configured (in T511, T539 etc ) and stores in the wage type of the infotype record IT0008. When there is a change to the monthly working hours (in P0007-MOSTD), the system displays message (RP371) - 'Annual salary has changed, please check your entry' in IT 0008 Basic Pay and the current saved record is overwritten with a recalculated annual salary based on the period salary.
Example, Employee on full time work schedule, current IT 0008 (saved) - Annual salary is EUR 50000.00 and therefore WT Basic salary is EUR 4666.67.
In a scenario where the employee moves from full time to part-time and where there is change to the monthly working hours, the annual salary is being recalculated based on the period salary (which is 4666.67) and displays EUR 50000.04 rather than EUR 50000.00.
Any ideas why this is happening and any help is much appreciated.