condition mean min max ZT0-3 16.799999999999997 16.799999999999997 16.799999999999997 ZT4-7 1.3 1.3 1.3 ZT8-11 25.349999999999998 25.349999999999998 25.349999999999998 ZT12-15 14.399999999999999 14.399999999999999 14.399999999999999 ZT16-19 9.55 9.55 9.55 ZT20-23 20.35 20.35 20.35