condition mean min max ZT0-3 2.990635 2.990635 2.990635 ZT4-7 1.43991 1.43991 1.43991 ZT8-11 2.02837 2.02837 2.02837 ZT12-15 2.51699 2.51699 2.51699 ZT16-19 4.611205 4.611205 4.611205 ZT20-23 3.115825 3.115825 3.115825