condition mean min max ZT0-3 3.0 3.0 3.0 ZT4-7 7.8 7.8 7.8 ZT8-11 22.05 22.05 22.05 ZT12-15 22.6 22.6 22.6 ZT16-19 15.649999999999999 15.649999999999999 15.649999999999999 ZT20-23 44.8 44.8 44.8