Bonjour,
il s'agit d'une macro accessible par Alt+F11
Option Explicit
Dim cell
Private Sub Worksheet_Change(ByVal Target As Range)
If Intersect(Target, Range("A1:A" & Range("A1").End(xlDown).Row)) Is Nothing Then
Set cell = Range("A1:A" & Range("A1").End(xlDown).Row).Find(Target, lookat:=xlWhole)
If Not cell Is Nothing Then
Target.Offset(0, 1) = cell.Offset(0, 1).Value
End If
End If
End Sub