Getting different employee counts using the same filters

Summary:

I was getting inconsistent employee counts on a dashboard I was working on so I created 2 different analyses from different subject areas and applied the same filters and saw that the count of distinct person numbers was different. If I remove all the filters, I get congruent counts. I added the filters back in one at a time, and the problem occurred when I added Job Code NOT IN… When I remove that filter, the counts are equal again. Can anyone tell me why this is happening or how to fix it. My dashboard requires counts