condition mean min max ZT0-3 5.62598 5.62598 5.62598 ZT4-7 3.76775 3.76775 3.76775 ZT8-11 4.08028 4.08028 4.08028 ZT12-15 4.39837 4.39837 4.39837 ZT16-19 6.028885 6.028885 6.028885 ZT20-23 5.61688 5.61688 5.61688