' evaluate the number of business days between two dates
'
Function BusinessDateDiff(ByVal StartDate As Date, ByVal EndDate As Date, _
Optional ByVal SaturdayIsHoliday As Boolean = True) As Long
Dim incr As Date

' ensure we don't take time part into account
StartDate = Int(StartDate)
EndDate = Int(EndDate)

' incr can be +1 or -1
If StartDate < EndDate Then incr = 1 Else incr = -1

Do Until StartDate = EndDate
' skip to previous or next day
StartDate = StartDate + incr
If Weekday(StartDate) <> vbSunday And (Weekday(StartDate) <> vbSaturday _
Or Not SaturdayIsHoliday) Then
' if it's a weekday add/subtract one to the result
BusinessDateDiff = BusinessDateDiff + incr
End If
Loop
' when the loop is exited the function name
' contains the correct result

End Function