Update Rules

Hello Guys,

I'm uploading information from one cube to another and the as follow:

data to be uploaded

ZXX 10 20

ZXX 20 40

as a result upload ZXX 30 60 which is correct, but I need to fill up a characteristics asking to the total 30 and 60, but I think that the routine at update rules is reading record by record. Is there any way to summarize the records first?

Regards,

Iván.