condition mean min max ZT0-3 1.90697 1.4296250000000001 2.207415 ZT4-7 2.3934699999999998 2.3934699999999998 2.3934699999999998 ZT8-11 2.1467 2.1467 2.1467 ZT12-15 2.1259125 1.86787 2.3839550000000003 ZT16-19 2.200245 2.200245 2.200245 ZT20-23 3.749035 3.749035 3.749035