yes you would use a conditional statement like
if Category="ACT' and [month]<= 8 then running_sum(...)
elseif Category <> "ACT' then running_sum(...) end
Since you did not include your twbx workbook I can not be more specific - you will have to check it out
thanks! jim that's very useful logic and confirmation to my hyphotesis.
Glad to help out - if this was helpful please mark my reply helpful or correct