condition mean min max ZT0-3 11.3669 11.3669 11.3669 ZT4-7 6.758005 6.758005 6.758005 ZT8-11 3.675815 3.675815 3.675815 ZT12-15 6.69703 6.69703 6.69703 ZT16-19 12.689499999999999 12.689499999999999 12.689499999999999 ZT20-23 7.122755 7.122755 7.122755