【VBA】重複データをエラー処理付きで非表示にする方法

Option Explicit
Sub HideDuplicateData()
    Dim ws As Worksheet
    Set ws = ThisWorkbook.Sheets("Sheet1")
    Application.ScreenUpdating = False
    
    Dim lastRow As Long, i As Long, j As Long
    lastRow = ws.Cells(ws.Rows.Count, 1).End(xlUp).Row
    
    For i = lastRow To 2 Step -1
        If IsDuplicate(i, ws) Then
            ws.Rows(i).Hidden = True
        End If
    Next i
    Application.ScreenUpdating = True
End Sub

Function IsDuplicate(row As Long, ws As Worksheet) As Boolean
    Dim j As Long
    For j = row - 1 To 2 Step -1
        If ws.Cells(j, 1).Value = ws.Cells(row, 1).Value Then
            IsDuplicate = True
            Exit Function
        End If
    Next j
    IsDuplicate = False
End Function