How to carry forward the backlog value and calculate the value for 'Hired on backlog'

[Anonymous]

Hi,

Scenario 1:

How to carry forward my backlog value (Target - (Total Hired)) of the first row to the second row of a particular key?

For a same key. if there's a backlog value, then it is forwarded to the next row of the same key.

Scenario 2:

If there's a backlog value, then if any hiring takes place for the particular month, then my value of Hired (Count(Candidate_ID) based on Key) should be placed in Hired on Backlog.

This is the sample output. I have also attached a sample dataset. Please help