??? ?? ??? ??? ???? ??????? ?? ?????? ???? ??? ???, ???? ????? ?? ??? ???? ??? ?????? ???? ??????? ?? ???? ??? ???? ???? ??? ???? ?? ??? ???? ???? ????? ??????? ??? ????? ???? ???? ???? ??????? ?????? ?? ????? ?????? even more, a firm's book benefit is calculated working with its historical facts,