How to divide a specific number of rows with all the rows from the same column?

[Yean]

Hello everyone. I have data as shown above and what i need to do is to get the percentage for each level of each dept based on yearmonth. So i need to count the number of rows for each level of each dept based on yearmonth, and then divide with all the rows for each dept based on yearmonth. I've been trying for few days already but I can't seem to find the correct qlik sense expression for this. Can anyone help me? Thank you so much in advance.

[Mario_ES]

Try with Set Analysis.

[Yean]

I did try but i still can't get it. I actually tried to calculate the number of rows for each level and total number of rows regardless of the level by using sql first and the write the set analysis in qlik sense. The table below is what i calculated first in sql. I added the RowNumber column cause I only want to add the NoOfAllLevel for distinct month.

And then i wrote the set analysis like this :

sum([NoOfLevel]) / sum({$<[RN] = {'1'}>}[NoOfAllLevel]) *100

However, I ended up only getting the chart for first level shown in the table which is "Level 2", Level 3 and 5 didn't show in the chart at all.

[Yean]

Hello~ Really no one knows?