condition mean min max ZT0-3 0.45267829025 0.427343429 0.4780131515 ZT4-7 1.2698476835 0.5257507100000001 2.013944657 ZT8-11 6.886843871 5.267532964 8.506154777999999 ZT12-15 8.41864108625 8.196288918 8.6409932545 ZT16-19 2.9761809185 2.3787998445000005 3.5735619924999997 ZT20-23 1.49085977875 1.229424576 1.7522949815000002