Adding a Credit column to Manage Groups and All Invoices Page

When viewing the groups in the Manage Groups page, could we please get a column option to display their "Credit" balance. That way I could sort by groups that only have a credit issued.

Adding a credit column to the Invoices > All Invoices view as well would also help us ensure that the balance totals match at a quick glance without having to go to the Manage Groups section to see credits.