condition mean min max ZT0-3 22.064516666666666 19.80205 23.66235 ZT4-7 14.959399999999999 14.959399999999999 14.959399999999999 ZT8-11 19.8185 19.8185 19.8185 ZT12-15 33.66665 30.672 36.6613 ZT16-19 31.3601 31.3601 31.3601 ZT20-23 34.17205 34.17205 34.17205