Black swan events are exceptionnel events that are not expected by most market adhérent. They parti price moves well outside ordinaire expectations or typical market movements.????? ??????? ?? ?????? ???? ?????? ?? ????? ?? ????? ?????? ??? ????? ??? ????? ??????? ??? ?? ???? ??? ??????? ???? ????? ????????? ????????, ??? ?? ??? ???? ????? ???? ??