I have a list of over 10,000 employee with 7 levels supervisor relationship from our HR system. The list looks like:

Joe reports to Mary
Sandar reports to Mary
Peter reports to Philip
Viola reports to Mary
Mary reports to David
Saly reports to Mary
Philip reports to David

I would like to produce an excel grouping or hierarchy that looks like:

David
--Mary
----Joe
----Sandra
----Saly
----Viola
--Philip
----Peter

How can I achieve this?