condition mean min max ZT0-3 30.85 30.85 30.85 ZT4-7 21.7 21.7 21.7 ZT8-11 4.6 4.6 4.6 ZT12-15 27.200000000000003 27.200000000000003 27.200000000000003 ZT16-19 35.85 35.85 35.85 ZT20-23 29.549999999999997 29.549999999999997 29.549999999999997