Pl attach some dataset or workbook
Hi, M B
It seems a general question, but without seeing your underlying data structure, it is not easy to provide a solution in couple of lines. But I think you need some level of data reshape by joining your data to a calendar table to achieve this. Or if you only need to look at one month every time, you need calculation to compare the start date of the people and the selected month.
If you could provide a sample data set or workbook will be more helpful