How is it possible to compute the difference between the two dates, only computing working days and skipping weekends and holidays? Simple math is no longer useful here, and DAX does not offer a predefined function.
A solution to this scenario requires a date table – more details here – with a specific column, IsWorkingDay, which indicates whether that particular day is a working day or not. The following figure shows an example:
Another good use of date tables (AKA calendar tables), which are also quite useful in T-SQL queries.