condition mean min max ZT0-3 1.7698798333333332 0.9264345 2.319215 ZT4-7 1.81129 1.81129 1.81129 ZT8-11 1.859815 1.859815 1.859815 ZT12-15 6.7348275 6.179855 7.2898 ZT16-19 4.67152 4.67152 4.67152 ZT20-23 4.232065 4.232065 4.232065