Pivot Table percentage calculation not working with column headers and filter

[ahmetkara]

I have a pivot table where I'm getting the count of each "Failure" category.

=Count(Failure)

I can calculate the percentage per category if I just have Wk" as 'per week' column headers.

=Num(Count(Failure)/Count(Total<Wk>(Failure)),'##0.0%')

I can also calculate the percentage per category if I filter the "failures" per another column "AM".

=Num(Count( { <AM={AM84}> } Failure) / Count( TOTAL {< AM={AM84} >} Failure),'##0.0%')

However, whenever I try to do a pivot table combining both the "Wk" weekly column headers and the "AM84" filter, I cannot seem to get the percentage calculation to work. I have been trying to tweak the following with no luck:

=Num(Count( { <AM={AM84}> } Failure) / Count( TOTAL {< {Wk} > , < AM={AM84} >} Failure),'##0.0%')

Any help would be appreciated.

Regards