condition mean min max ZT0-3 12.940433333333333 11.7534 14.744399999999999 ZT4-7 14.86295 14.86295 14.86295 ZT8-11 16.1734 16.1734 16.1734 ZT12-15 19.649075 18.15495 21.1432 ZT16-19 16.17005 16.17005 16.17005 ZT20-23 14.586 14.586 14.586