Antonio, while you can easily create the % margin field you're talking about, I can't think of a way to append this to the bottom of the account name field so they all appear in one column. Generally speaking Tableau is used to visualize your data; it is not set up to append records to the underlying data, which is what it sounds like you're wanting to do. If I'm misunderstanding this let me know.
yes you are right. thanks.
i ended up making sure the data include that piece of information.