condition mean min max ZT0-3 27.861525 26.636850000000003 29.086199999999998 ZT4-7 34.56275 34.56275 34.56275 ZT8-11 21.16525 21.16525 21.16525 ZT12-15 0 0 0 ZT16-19 30.71085 30.71085 30.71085 ZT20-23 26.5312 26.5312 26.5312