=IF(ISERROR(DSUM(Combined!$A$1:$O$1612,12,$M$1:$P$2)/$B5)=TRUE,"",DSUM(Combined!$A$1:$O$1612,12,$M$1:$P$2)/$B5)
The sections of the code that are underlined above are what I would like to replace with the row function you gave me. How would I do that?