Sub compter_uniques()
Dim pl As Range, DerLig As Double, i As Double, Nb As Double
Set pl = Range("A2:A" & [A65536].End(xlUp).Row)
pl.Name = "base"
DerLig = [A65000].End(xlUp).Row
For i = DerLig To 1 Step -1
Nb = Evaluate("COUNTIF(base,""" & Cells(i, 1) & """)")
Cells(i, 1) = IIf(Len(Cells(i, 1) & Nb) > 20, Left(Cells(i, 1), 20 - Len(CStr(Nb))) & Nb, Cells(i, 1) & Nb)
Next i
End Sub