condition mean min max ZT0-3 2.9557283333333335 1.424195 4.22162 ZT4-7 1.493695 1.493695 1.493695 ZT8-11 3.4234 3.4234 3.4234 ZT12-15 3.2380575 2.29818 4.177935 ZT16-19 3.432915 3.432915 3.432915 ZT20-23 3.78648 3.78648 3.78648