'=xdupsv(A2:A11)
Function xDupsV(fCol As Range, Optional offsetCol As Integer = 1)
Dim a, r1 As Range, r2 As Range, c As Range, cc As Range, sNum As Long, i As Long, j As Long
Application.Volatile True
Set r1 = fCol
Set r2 = r1.Offset(, offsetCol)
ReDim a(1 To 1)
For Each c In...