Power BI measure - avoid table with ID on every date between startdate and enddate >10.000.000 rows

I have a isue.
I have 3 tables
1 -->calender table with date, and yearmont
1 -->employment, ID, startdate, enddate, organisationID, Group, employmentdate
1 --> organisation, OrganisationID, name

I want to show how many employments, i've got in a specific month but i have not found a solution without making af fact table with employments.ID and every date between startdate and enddate

then I can make a measure to count number of employmens in a given month

I also need a dynamic group for age( >10 year, 10-20 years ...), group for employment ( >10 year, 10-20 years ...)
is it possible in the current version of power BI Desktop?