condition mean min max ZT0-3 1.7895266666666667 1.55477 2.01084 ZT4-7 2.51633 2.51633 2.51633 ZT8-11 0.959571 0.959571 0.959571 ZT12-15 0.7644015 0.720793 0.80801 ZT16-19 0.6515365 0.6515365 0.6515365 ZT20-23 0.513151 0.513151 0.513151