I have this problem. I have a list of contingen workers, each worker has a starting date and end date.
I would like to create a Bar Chart for the year 2017 (Jan to Dec) and count how many active workers I have in that specific month. I can use/count distinct the ID or Name of the worker. The problem is that in some cases I have a worker that started in Oct 2016 and will end his contract in Sep 2018 and in that case the worker will be active each month during 2017, but I have other cases where the worker started in Dec 2016 and will end his contract in Jan 2017, so I can only count that worker as active in Jan 2017 but not the rest of the month of 2017.