condition mean min max ZT0-3 8.837254606666667 8.021119316333333 9.653389897 ZT4-7 8.429662526 8.321955134 8.537369918 ZT8-11 11.297802271666667 9.990295116666667 12.605309426666667 ZT12-15 9.935086112833334 9.803201832000001 10.066970393666667 ZT16-19 11.871921061 9.646631042000001 14.09721108 ZT20-23 11.321103449999999 10.85652075 11.78568615