condition mean min max ZT0-3 1.123918 0.608089 1.389025 ZT4-7 0.392638 0.392638 0.392638 ZT8-11 0.43095649999999996 0.43095649999999996 0.43095649999999996 ZT12-15 0.37092749999999997 0.3444985 0.3973565 ZT16-19 0.555101 0.555101 0.555101 ZT20-23 0.9214665 0.9214665 0.9214665