condition mean min max ZT0-3 20.275299999999998 20.275299999999998 20.275299999999998 ZT4-7 19.724249999999998 19.724249999999998 19.724249999999998 ZT8-11 24.42655 24.42655 24.42655 ZT12-15 25.5842 25.5842 25.5842 ZT16-19 22.779 22.779 22.779 ZT20-23 26.441033333333333 26.441033333333333 26.441033333333333