condition mean min max ZT0-3 2.4986550000000003 2.4986550000000003 2.4986550000000003 ZT4-7 2.155755 2.155755 2.155755 ZT8-11 2.175185 2.175185 2.175185 ZT12-15 1.738725 1.738725 1.738725 ZT16-19 2.28087 2.28087 2.28087 ZT20-23 1.720345 1.720345 1.720345