condition mean min max ZT0-3 68.745043 68.745043 68.745043 ZT4-7 23.941527999999998 23.941527999999998 23.941527999999998 ZT8-11 78.8060175 78.8060175 78.8060175 ZT12-15 117.50296599999999 117.50296599999999 117.50296599999999 ZT16-19 290.4954525 290.4954525 290.4954525 ZT20-23 223.63855 223.63855 223.63855