condition mean min max ZT0-3 3.07618710525 2.7092745565 3.4430996539999996 ZT4-7 2.54141656475 1.6391619655 3.443671164 ZT8-11 4.1814706885 3.953140631 4.409800746 ZT12-15 4.6617782742500005 4.275912654000001 5.0476438945 ZT16-19 7.0937694245 5.4714918095 8.7160470395 ZT20-23 14.279007224999999 12.312783544999998 16.245230905