Sub ColorPlage()
Application.ScreenUpdating = False
couleur = 36
Set mondico = CreateObject("Scripting.Dictionary")
For Each Cel In Range("K2:K" & Range("K65536").End(xlUp).Row)
If Not mondico.Exists(Cel.Value) Then mondico.Add Cel.Value, Cel.Value
Next
For Each Item In mondico.items
Set c = Columns("K").Find(Item, LookIn:=xlValues)
If Not c Is Nothing Then
firstAddress = c.Address
ld = c.Row: lf = ld - 1
Do
lf = lf + 1
Set c = Columns("K").FindNext(c)
Loop While Not c Is Nothing And c.Address <> firstAddress
End If
Range(Cells(ld, 1), Cells(lf, 11)).Interior.ColorIndex = couleur
couleur = IIf(couleur = 36, 34, 36)
lf = 0
Next
Application.ScreenUpdating = True
End Sub