condition mean min max ZT0-3 6.3598775 6.215085 6.50467 ZT4-7 3.943345 3.943345 3.943345 ZT8-11 3.32662 3.32662 3.32662 ZT12-15 0 0 0 ZT16-19 4.76097 4.76097 4.76097 ZT20-23 4.9635 4.9635 4.9635