Private Sub Worksheet_Change(ByVal Target As Range)
Dim i As Long
If Target.Address = "$C$7" Then
Application.ScreenUpdating = False
Range("E1:IV1").EntireColumn.Hidden = False
For i = 5 To Range("IV13").End(xlToLeft).Column
If IsDate(Cells(13, i).Value) Then
If Month(Cells(13, i).Value) <> Application.Match(Target.Value, Sheets("List Mois").Range("January"), 0) Then
Cells(13, i).EntireColumn.Hidden = True
End If
End If
Next i
Application.ScreenUpdating = True
End If
End Sub