Bonsoir,
Une 'tite macro qui devrait faire l'affaire :
Sub Galopin()
Dim i%, s$
For i = 2 To Range("B" & Rows.Count).End(xlUp).Row
s = Cells(i, 2).Value
If Right(s, 1) = "3" Then
s = Mid(s, 1, 3) & "SWG" & Mid(s, 7)
With Worksheets(s)
Cells(i, 3).Value = .Range("B" & .Range("B" & Rows.Count).End(xlUp).Row - 1).Value
End With
End If
Next
A+