Count of Rows using Master Calendar

Hi , rinaemo 

Thanks for yoour quick response ! 

According to your description, you just want to calculate the number of people who are on the job in the middle of the year and month, and for your needs, I have implemented it in the above example, and it is according to your logic to calculate.

If you want to filter based on the year and month you choose, you just need to put [Date] in 'Calendar' in slicer, and then you can implement your needs,like this:

If this method does not meet your needs, you can provide us with  the desired output sample screenshot, so that we can better help you solve the problem.

Thank you for your time and sharing, and thank you for your support and understanding of PowerBI! 

Best Regards,

Aniya Zhang

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly