When the N: modifier is used, the rule will only be applied at the base or leaf level. The values of cells at higher levels will be calculated according to the consolidation hierarchies defined in the cube’s dimensions. In most cases, if a calculation can be performed just at the leaf level, it is more efficient to allow TM1 to simply consolidate the results, rather than performing the calculation at every level of the hierarchies.
If the C: modifier is used, the calculation will be applied to consolidated cells only. This can be useful to override the normal consolidation that the dimension hierarchies provide. However, this should be used with care to avoid over complicating the model. Suitable uses of the C: modifier might be to prevent the price being consolidated in our example:
[‘Price’]=C:0;
When a Dimension Calculation defines an N calculation or a C Calculation, this syntax is used in the resulting cube rule.
The lack of a modifier indicates that the calculation is to be applied at all levels. This is necessary for calculations such as ratios, percentages and averages, which usually cannot be consolidated and must be performed at each level of the dimensions’ hierarchies.
There is another modifier, S:, which is used when the rule is being used to ‘calculate’ string (text) value instead of a numeric value.