condition mean min max ZT0-3 26.299999999999997 26.299999999999997 26.299999999999997 ZT4-7 28.3 28.3 28.3 ZT8-11 40.5 40.5 40.5 ZT12-15 25.9 25.9 25.9 ZT16-19 27.45 27.45 27.45 ZT20-23 39.35 39.35 39.35