condition mean min max ZT0-3 26.950000000000003 26.950000000000003 26.950000000000003 ZT4-7 12.6 12.6 12.6 ZT8-11 15.649999999999999 15.649999999999999 15.649999999999999 ZT12-15 34.7 34.7 34.7 ZT16-19 26.35 26.35 26.35 ZT20-23 24.2 24.2 24.2