Private Sub Worksheet_Change(ByVal Target As Range)
Dim Ecart As Long, DerLig As Long, DerB As Long
Dim C As Range
Dim firtsaddress As String
DerB = Sheets(1).Range("B65500").End(xlUp).Row
If Intersect(Target, Sheets(1).Range("B1:B" & DerB)) Is Nothing Then Exit Sub
DerLig = Sheets(1).Range("A65500").End(xlUp).Row
With Sheets(1).Range("A1:A" & DerLig)
Set C = .Find(Target.Value)
If Not C Is Nothing Then
firstAddress = C.Address
Do
Ecart = DerLig - C.Row
Set C = .FindNext(C)
Loop While Not C Is Nothing And C.Address <> firstAddress
End If
Target.Offset(0, 1).Value = Ecart
End With
End Sub