condition mean min max ZT0-3 4.5516325 3.714955 5.38831 ZT4-7 2.740905 2.740905 2.740905 ZT8-11 4.70821 4.70821 4.70821 ZT12-15 0 0 0 ZT16-19 4.383274999999999 4.383274999999999 4.383274999999999 ZT20-23 4.65318 4.65318 4.65318