condition mean min max ZT0-3 9.659925 7.181675 14.1585 ZT4-7 2.4235835 2.4235835 2.4235835 ZT8-11 2.52909 2.52909 2.52909 ZT12-15 4.4680575000000005 4.078955 4.85716 ZT16-19 7.23793 7.23793 7.23793 ZT20-23 11.91115 11.91115 11.91115