It would be extremely useful to have the option to define a working days calendar (e.g. Monday–Friday, excluding weekends and optionally holidays) that can be used across the system.

This calendar should also be supported by the DATEDIFF formula, allowing users to calculate the number of working days between two dates instead of calendar days. This would greatly improve scheduling, deadline tracking, project management, and KPI reporting for businesses that operate on working days rather than calendar days.