condition mean min max ZT0-3 2.39779 2.359875 2.45047 ZT4-7 6.348535 6.348535 6.348535 ZT8-11 18.81365 18.81365 18.81365 ZT12-15 15.539525000000001 13.161650000000002 17.9174 ZT16-19 9.924425 9.924425 9.924425 ZT20-23 7.23596 7.23596 7.23596