condition mean min max ZT0-3 3.4574149999999997 3.053355 3.8614749999999995 ZT4-7 4.20908 4.20908 4.20908 ZT8-11 26.39155 26.39155 26.39155 ZT12-15 0 0 0 ZT16-19 23.249049999999997 23.249049999999997 23.249049999999997 ZT20-23 12.0688 12.0688 12.0688