condition mean min max ZT0-3 27.378094 27.378094 27.378094 ZT4-7 29.1670885 29.1670885 29.1670885 ZT8-11 25.6910945 25.6910945 25.6910945 ZT12-15 34.156613 34.156613 34.156613 ZT16-19 53.770299 53.770299 53.770299 ZT20-23 71.2085275 71.2085275 71.2085275