Option Explicit

Private sinFTime(1 To 2) As Single, sinETime(1 To 2) As Single
Private Sh As Worksheet

Sub ScreenUpdating3()
    Dim i As Long, ii As Long
        Set Sh = Worksheets(2)
        Sh.Cells.ClearContents
        For i = 31 To 40
            Call TestE
            Call TestF
            For ii = 1 To 2
                Worksheets(1).Cells(i, ii + 1).Value = sinETime(ii)
            Next
        Next
End Sub

Private Sub TestE()
    Dim i As Long, c As Long
    sinFTime(1) = Timer
    For i = 1 To 1000
        c = i
    Next
    sinETime(1) = Timer - sinFTime(1)
End Sub

Private Sub TestF()
    Dim i As Long, c As Long
    sinFTime(2) = Timer
    For i = 1 To 1000
        Application.ScreenUpdating = False
        c = i
        Application.ScreenUpdating = True
    Next
    sinETime(2) = Timer - sinFTime(2)
End Sub