Sub efface()
Dim t, cel As Range
t = Timer
For Each cel In Cells.SpecialCells(xlCellTypeConstants)
cel.Value = cel 'cel.Value
Next
MsgBox Timer - t
End Sub
Sub a()
Dim t, c As Range
t = Timer
For Each c In ActiveSheet.UsedRange
c.Value = c 'c.Value
Next
MsgBox Timer - t
End Sub