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Public Function TimePeriod(StartTime As String, FinishTime As String) As String
Dim MyDays As String
Dim MyHours As Single
Dim MyMinutes As Single
Dim MySeconds As Single
Dim ToRemove As Long
Dim sDate As Date
Dim sTime As String
Dim fDate As Date
Dim fTime As String

sDate = Format(Mid(StartTime, 1, InStr(StartTime, " ") - 1), "dd/mm/yy")
sTime = Format(Mid(StartTime, InStr(StartTime, " ") + 1), "hh:mm:ss")
fDate = Format(Mid(FinishTime, 1, InStr(FinishTime, " ") - 1), "dd/mm/yy")
fTime = Format(Mid(FinishTime, InStr(FinishTime, " ") + 1), "hh:mm:ss")



MySeconds = DateDiff("s", sDate & " " & sTime, fDate & " " & fTime)
MyDays = Fix(((MySeconds / 60) / 60 / 24))
ToRemove = MyDays * 24 ' hours
MyHours = Fix(((MySeconds / 60) / 60) - (MyDays * 24))
ToRemove = Fix((ToRemove * 60) + (MyHours * 60)) 'minutes
MyMinutes = Fix((MySeconds / 60) - ToRemove)
ToRemove = Fix((ToRemove * 60) + (MyMinutes * 60)) 'seconds
MySeconds = MySeconds - ToRemove



TimePeriod = "Days=" & MyDays & " Hours=" & MyHours & " Minutes=" & MyMinutes & " Seconds=" & MySeconds
TimePeriod = MyHours + (MyDays * 24) & ":" & MyMinutes & ":" & MySeconds

End Function