condition mean min max ZT0-3 4.04403845525 2.4829325 5.6051444104999995 ZT4-7 11.95733002225 9.3304146445 14.5842454 ZT8-11 23.3768330525 18.785094174999998 27.968571930000003 ZT12-15 20.371780772500003 18.417691645 22.3258699 ZT16-19 17.1965119975 15.714402605 18.67862139 ZT20-23 20.2721291625 18.98642797 21.557830355