This can occur if there are multiple Historical Data Items linked to the same employee data item:

1. In Payroll, select Setup, Historic Data Item.
2. Select C for Change and then enter the Historic Data Item.
3. Page down or select option 8.
4. In the Calculation, select S for Scroll
5. Scroll through until you find the calculation commands.
6. Note the Employee Data Item being used in the calculation and whether this Employee Data item is in field 8 of another Historical Data Item.
7. Hit Escape and then R to remove.
8  Remove the calculation line where the Employee Data Item does not belong.