condition mean min max ZT0-3 33.29155 33.29155 33.29155 ZT4-7 25.7616 25.7616 25.7616 ZT8-11 19.6719 19.6719 19.6719 ZT12-15 21.75275 21.75275 21.75275 ZT16-19 28.5764 28.5764 28.5764 ZT20-23 36.1983 36.1983 36.1983