condition mean min max ZT0-3 88.488575 84.5298 92.44735 ZT4-7 74.2401 74.2401 74.2401 ZT8-11 22.28715 22.28715 22.28715 ZT12-15 0 0 0 ZT16-19 32.6759 32.6759 32.6759 ZT20-23 69.70765 69.70765 69.70765