condition mean min max ZT0-3 14.83785 14.83785 14.83785 ZT4-7 9.45718 9.45718 9.45718 ZT8-11 6.908035 6.908035 6.908035 ZT12-15 9.090285 9.090285 9.090285 ZT16-19 14.9495 14.9495 14.9495 ZT20-23 16.427799999999998 16.427799999999998 16.427799999999998