Function MaDuree(deb#, fin#)
Dim t1#, t2#, minute&, t#
t1 = TimeValue("8:0")
t2 = TimeValue("17:0")
For minute = 1440 * deb To 1440 * fin
t = TimeValue(Format(minute / 1440, "h:m"))
If t >= t1 And t <= t2 Then MaDuree = MaDuree + 1
Next
MaDuree = MaDuree / 1440
End Function