condition mean min max ZT0-3 1.93606507925 1.8180130840000002 2.0541170745 ZT4-7 4.977400548 3.0956106345 6.8591904615 ZT8-11 18.4178658955 13.698265080999999 23.137466709999998 ZT12-15 21.088083722500002 17.431007775 24.74515967 ZT16-19 14.688672050000001 14.418434765 14.958909335 ZT20-23 15.3830055175 14.76767769 15.998333344999999