condition mean min max ZT0-3 0.9015562655 0.629816618 1.173295913 ZT4-7 2.9189181745 1.636371666 4.201464683 ZT8-11 10.8232404505 9.949137431 11.69734347 ZT12-15 28.5238637025 24.609624500000002 32.438102905 ZT16-19 21.4493902925 20.801279459999996 22.097501125 ZT20-23 19.682576535 18.116323195 21.248829875