condition mean min max ZT0-3 12.648 12.648 12.648 ZT4-7 11.468 11.468 11.468 ZT8-11 15.6829 15.6829 15.6829 ZT12-15 18.60085 18.60085 18.60085 ZT16-19 21.3604 21.3604 21.3604 ZT20-23 14.457550000000001 14.457550000000001 14.457550000000001