Key Figure calculation, formula to check for ONLY values (NOT NULL) in attribute on Planning Object.

[SoniaMarwah]

I am trying to configure a keyfigure with checks such as: 

Condition 1: At customer product and shipto level, XYZPROP key figure has 0 value in for CURRENT TO 13 PERIODS- for which I created an helper key figure. with IBP_DYNAMIC_RAGGR("ABC@MTHPRODLOCCUSTWE",''SUM'', 0, 13, ''CURRENTFUTURE'')  and Condition2: If attribute SHIPFROMDEFAULTLOC at customer product loc and shipto level is NOT blank, then check the SHIPFROMDEFAULTLOC value is equal to locid then assign ZWEPROPSTAT with the ZWEADJUSTEDACTUALSQTY in the future buckets to that level record.

What formula in the key figure calculation would work to check for planning objects that has values (NOT NULL) in attribute on Planning Object? Per my understanding, we can only use static value. Is that true?