Counting time ranges within a range

Thank you for that. It came to the common conclusion even though it logically looked correct Excel hates midnight!

Many thanks for your help.

PS If this helps I have a macro that if indeed anyone has an already populated file and needs a similar solution this will add a second to all issues of midnight.

Sub change_midnight()

    Cells.Replace What:="00:00:00", Replacement:="00:00:01", LookAt:=xlPart, _
        SearchOrder:=xlByRows, MatchCase:=False
End Sub