condition mean min max ZT0-3 226.959112 226.959112 226.959112 ZT4-7 141.56664899999998 141.56664899999998 141.56664899999998 ZT8-11 170.36541 170.36541 170.36541 ZT12-15 194.8673215 194.8673215 194.8673215 ZT16-19 275.8160855 275.8160855 275.8160855 ZT20-23 330.81588650000003 330.81588650000003 330.81588650000003