condition mean min max ZT0-3 1.0006271666666666 0.698661 1.3450950000000002 ZT4-7 0.4093825 0.4093825 0.4093825 ZT8-11 0.4227625 0.4227625 0.4227625 ZT12-15 1.087231 0.8800955 1.2943665 ZT16-19 0.7521675 0.7521675 0.7521675 ZT20-23 1.8761999999999999 1.8761999999999999 1.8761999999999999