condition mean min max ZT0-3 2.2504775 1.881785 2.61917 ZT4-7 1.7685460000000002 1.7685460000000002 1.7685460000000002 ZT8-11 0.714792 0.714792 0.714792 ZT12-15 0 0 0 ZT16-19 1.72313 1.72313 1.72313 ZT20-23 4.54886 4.54886 4.54886