How to calculate layers from a dependent set of data?

[zb134]

Sorry about the title but it's hard to condense it to a sentence and make sense.

This is what I am trying to achieve (col C):

Name	Reports To	Layers From D
A	B	3
B	F	2
C	F	2
D	-	0
E	B	3
F	D	1

Given Col A and Col B, I want a calculated column to see how far a person is in the reporting structure from D. So for example, C reports to F who reports to D, so 2 layers from D.

From a programming perspective, I think the approach is to go iteratively go through each person in COl A and use a counter to add +1 until person D is reached. But I am lost on how to implement it in PBI. Any suggestions?

[Boofus · Accepted solution]

 using path function