condition mean min max ZT0-3 12.55 12.55 12.55 ZT4-7 1.6 1.6 1.6 ZT8-11 14.75 14.75 14.75 ZT12-15 25.799999999999997 25.799999999999997 25.799999999999997 ZT16-19 25.7 25.7 25.7 ZT20-23 25.35 25.35 25.35