condition mean min max ZT0-3 23.9 23.9 23.9 ZT4-7 27.6 27.6 27.6 ZT8-11 25.4 25.4 25.4 ZT12-15 30.950000000000003 30.950000000000003 30.950000000000003 ZT16-19 35.3 35.3 35.3 ZT20-23 46.75 46.75 46.75