condition mean min max ZT0-3 17.018166666666666 13.668849999999999 18.7518 ZT4-7 8.63223 8.63223 8.63223 ZT8-11 7.64195 7.64195 7.64195 ZT12-15 23.325125 21.891 24.75925 ZT16-19 25.0426 25.0426 25.0426 ZT20-23 21.8784 21.8784 21.8784