condition mean min max ZT0-3 31.098775 29.6781 32.51945 ZT4-7 17.399549999999998 17.399549999999998 17.399549999999998 ZT8-11 19.19965 19.19965 19.19965 ZT12-15 0 0 0 ZT16-19 35.4184 35.4184 35.4184 ZT20-23 35.349149999999995 35.349149999999995 35.349149999999995