condition mean min max ZT0-3 33.1464 33.1464 33.1464 ZT4-7 28.4052 28.4052 28.4052 ZT8-11 28.7168 28.7168 28.7168 ZT12-15 26.6569 26.6569 26.6569 ZT16-19 28.2605 28.2605 28.2605 ZT20-23 31.81505 31.81505 31.81505