ABS function in Management Reporter 2012

Hi,

I have a question on using the ABS function in Management Reporter.2012. I am using the following formula:

IF C=0 THEN 0 ELSE D/ABS(C)

Management Reporter doesn't accept this formula, but if remove the ABS function it has nor problem saving my column format.

Anyone has any idea what may be wrong with the formula?

Please help.

Thanks

Amir