condition mean min max ZT0-3 34.2617542475 29.175657035 39.34785146 ZT4-7 4.645982796 2.959991429 6.331974163 ZT8-11 1.9385645525000001 1.8410972585 2.0360318465000002 ZT12-15 1.10055848975 1.0507260085 1.150390971 ZT16-19 1.34230682625 0.9514839265 1.733129726 ZT20-23 2.2100747765 2.17102152 2.249128033