Considere:
Sub dural()
Dim rng As Range, r As Range
Set rng = Range("C:C").Cells.SpecialCells(xlCellTypeConstants, xlNumbers)
For Each r In rng
r.Value = r.Value + 24
Next r
Set rng = Range("E:E").Cells.SpecialCells(xlCellTypeConstants, xlNumbers)
For Each r In rng
r.Value = r.Value + 1
Next r
End Sub
Detecta automaticamente os limites da operação.