condition mean min max ZT0-3 20.22955 20.22955 20.22955 ZT4-7 10.076004999999999 10.076004999999999 10.076004999999999 ZT8-11 11.59085 11.59085 11.59085 ZT12-15 15.29375 15.29375 15.29375 ZT16-19 16.5518 16.5518 16.5518 ZT20-23 22.89875 22.89875 22.89875