SSRS Question

I have to perform a simple division depending on two fields from a table. I am taking care not dividing by zero but for some reason it is giving me NAN.

Please find the expression below. 

= iif(IsNothing(Fields!Numerator.Value), nothing , iif(Fields!numerator.Value = 0, iif(Fields!Denominator.Value = 0, nothing , 0),(Fields!Numerator.Value/Fields!Denominator.Value)*100))

Also Please help with the expression which will take care of the issues.

Thanks,

Amit.