Null Results for Calculations Using SAP BW Data Sources
When using a SAP BW data source, the expression
you use in your calculation is evaluated as a null value if your expression
contains a null item. For example, in the calculation some_expression
= result, the result is null if a row or column that the expression
references includes a null value.
To avoid obtaining null values as the result of your calculations, suppress null values before you create the calculation.