condition mean min max ZT0-3 6.442005 6.442005 6.442005 ZT4-7 4.572345 4.572345 4.572345 ZT8-11 4.628145 4.628145 4.628145 ZT12-15 4.76848 4.76848 4.76848 ZT16-19 6.67673 6.67673 6.67673 ZT20-23 4.43488 4.43488 4.43488