Sub InsertRowsAtValueChangeColumnB()
  Dim X As Long, LastRow As Long
  Const DataCol As String = "B"
  Const StartRow = 2
  LastRow = Cells(Rows.Count, DataCol).End(xlUp).Row
  Application.ScreenUpdating = False
  For X = LastRow To StartRow + 1 Step -1
    If Cells(X, DataCol).Value <> Cells(X - 1, DataCol) Then Rows(X).Insert
  Next
  Application.ScreenUpdating = True
End Sub

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