The following expression returns the number of days, excluding Saturdays and Sundays, between the start date and end date.
[EndDate] - [StartDate] + 1 - (DateDiff("ww", [StartDate], [EndDate], 7) - (Weekday([StartDate]) = 7)) - (DateDiff("ww", [StartDate], [EndDate], 1) - (Weekday([StartDate]) = 1))
If you need to exclude holidays too, you can create a table "tblHolidays' with a date/time field "HolidayDate" to store the holiday dates and deduct the number of holiday days from the above expression with:-
- DCount("*","[tblHolidays]","[HolidayDate] between DateValue('" & [StartDate] & "') and DateValue('" & [EndDate] & "')")
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