Average Days in certain statuses

Summary

Average counting rows not distinct IDs

Content

Hi,

I am trying to adjust a formula in a column to produce the average days candidates spend in certain statuses, the problem with my formula is that it adds all of the days the candidates were in those statuses but then divides by the number if rows that it finds results on, instead of dividing by the distinct count of candidate IDs to get a true average. I am doing this in a column so that I can get the result in a tile. 
Below is an example of what is doing right now, it is adding the average duration days in red and dividing by the sum of candidate IDs, I need it to sum distinct candidate IDs.