The length of a field containing bracketed-DBCS data can range from 4 through 32 766 bytes (4 through 32 740 bytes if the field is variable length). The length of a DBCS-graphic field can range from 1 through 16 383 characters (1 through 16 370 characters if the field is variable length).
(3 characters x 2 bytes) + (shift-out + shift-in) = 8
(3 characters x 2 bytes) = 6