Excel VBA to use all filled cells in columns

Dim Final As Variant
    Final = Range("A1").End(xlDown).Row
With ActiveWorkbook.ActiveSheet.Range("A1:A" & Final & "")
    .Borders.LineStyle = xlContinuous
End With

Dim rcell As Range, rng As Range
  Set rng = Application.ActiveSheet.Range("D1:D" & Application.ActiveSheet.UsedRange.Rows.Count)
  For Each rcell In rng.Cells
  If IsNumeric(rcell.Value) = True Then
        rcell.Offset(0, 1).Font.Bold = True
  End If
Next rcell