This is a custom dimension of the type "Content Group". In this dimension, static information on a page is collected. "Exit Page" means that only exit pages (i.e., the last page of a visit) are taken into consideration.
"-" classifies all pages that are not assigned to a content group.
We cannot provide further information here, as each content group is configured in your Mapp Intelligence system.
For further questions please contact your Mapp Intelligence administrator.