Sub Importer_données()
Dim fichier As String, wbk As Workbook
fichier = Application.GetOpenFilename("Fichier Excel, *.xls; *.xlsx", , , , False)
If UCase(fichier) = "FAUX" Then Exit Sub
Set wbk = Application.Workbooks.Open(fichier, , False)
nomfichier = ActiveWorkbook.Name
Dim ws As Worksheet
For Each ws In ActiveWorkbook
Range("I3").Select
ActiveCell.FormulaR1C1 = _
"=MID(CELL(""nomfichier"",RC[-6]),FIND(""]"",CELL(""nomfichier"",RC[-6]))+1,3)"
Selection.AutoFill Destination:=Range("I3:I" & Range("A3").End(xlDown).Row), Type:=xlFillValues
Next ws
End Sub