What information cannot be displayed as a graph (line or bar) on the dashboard?

A form is used to capture prospect data for a yearly conference. The form needs to add prospects to a list after the submit, but it should not retroactively apply actions to prospects that have already filled out the form.
What automation tool would effectively achieve this goal?

A Prospect is a Visitor who has submitted an email address through a form or landing page on your site.

An Administrator wants to make a list of all prospects who complete the Contact Us form but only wants them to be added the first time they complete the form. If a prospect is ever removed from the list, they shouldn't be able to get added back to it.
What is a recommended way to create this type of list?

Arrange the steps to Access a Prospect Record: