negative value of ranks message

first sorry for my bad english and the issue is that; when i tried to add a rank and when i write a negative value for "minimum message number" there is an error. i attached error picture.

SQL ERROR [ mysqli ]

Out of range value for column 'rank_min' at row 1 [1264]

SQL

INSERT INTO phpbb_ranks (rank_title, rank_special, rank_min, rank_image) VALUES ('asd', 0, -20, 'VistaRanks/g_rank0.gif')

BACKTRACE

FILE: [ROOT]/includes/db/mysqli.php
LINE: 182
CALL: dbal->sql_error()

FILE: [ROOT]/includes/acp/acp_ranks.php
LINE: 90
CALL: dbal_mysqli->sql_query()

FILE: [ROOT]/includes/functions_module.php
LINE: 507
CALL: acp_ranks->main()

FILE: [ROOT]/adm/index.php
LINE: 74
CALL: p_master->load_active()