Luis,
If you click on a layout, you'll notice that the "Number of copies" field can contain a variable expression. This means that you could reference a field from your database that would contain the number of records, or use any kind of logical expressions to determine how many copies of a specific record.
Perhaps you could provide us with more information on the logic you intend to use to figure out the number of copies, so we can better help you to find a way to do it.
Regards,
Raphaël Lalonde Lefebvre