Turnover - Monthly Data Headcount

Hello! Thank you really much for your reply! 

Basically each table represent a new headcount file.

Let's imagine the second table i posted is the January Headcount. The third one let's say its from February and it shows that two persons joined the company. Lets say that the first table is the March Headcount and it shows that 3 persons left the company.

Every table i posted represents an Headcount file that is posted on the sharepoint folder and its automatically uploaded on the power bi makes me able to look at the "history" if I select a specific slicer on the report page. So this powerbi is a cumulative file that feeds on a lot of files.

The only way to see who left and who joined is when a new file is uploaded and we can compare if their employees id's are still there /or werent on the previous month. This would be easy on Excel with an XLOOKUP, but my manager needs it to be automatic on the powerbi.

The result that I would like would be that I could on the report table have a measure or some kind of table that shows specifically which employees left and which ones joined the company from one month to another. I need to calculate the difference from the total of employees in one month to another too. 

Im not able right now to show some pictures of visually what would look like, but I will try as soon as possible! 

Thank you so much for trying to help!