condition mean min max ZT0-3 27.933933333333332 22.080550000000002 32.20185 ZT4-7 15.4453 15.4453 15.4453 ZT8-11 18.04955 18.04955 18.04955 ZT12-15 20.8738 20.831049999999998 20.91655 ZT16-19 23.15785 23.15785 23.15785 ZT20-23 32.1881 32.1881 32.1881