condition mean min max ZT0-3 17.63815 17.63815 17.63815 ZT4-7 15.65015 15.65015 15.65015 ZT8-11 13.8543 13.8543 13.8543 ZT12-15 14.82685 14.82685 14.82685 ZT16-19 14.3103 14.3103 14.3103 ZT20-23 16.21385 16.21385 16.21385