condition mean min max ZT0-3 1.2014458333333333 0.2323805 2.43187 ZT4-7 0.4599985 0.4599985 0.4599985 ZT8-11 1.3973 1.3973 1.3973 ZT12-15 0.73178825 0.7194555 0.744121 ZT16-19 1.30537 1.30537 1.30537 ZT20-23 1.27302 1.27302 1.27302