Sub footnoteCharacters()
'Graham Mayor - http://www.gmayor.com - Last updated - 07 Jun 2017 
Dim oFNote As Footnote
Dim oRng As Range
Dim i As Integer, j As Integer
    For i = ActiveDocument.Footnotes.Count To 1 Step -1
        Set oFNote = ActiveDocument.Footnotes(i)
        Set oRng = oFNote.Reference.Characters.Last
        oRng.Text = " £$%" & oFNote.Range.Text & "%$£"
        DoEvents
    Next i
lbl_Exit:
    Set oFNote = Nothing
    Set oRng = Nothing
    Exit Sub
End Sub