condition mean min max ZT0-3 0.21166166666666666 0.094052 0.389589 ZT4-7 0.3837335 0.3837335 0.3837335 ZT8-11 0.6363795 0.6363795 0.6363795 ZT12-15 0.66393075 0.46663 0.8612314999999999 ZT16-19 0.431964 0.431964 0.431964 ZT20-23 0.22653 0.22653 0.22653