condition mean min max ZT0-3 22.5 22.5 22.5 ZT4-7 21.5 21.5 21.5 ZT8-11 3.8000000000000003 3.8000000000000003 3.8000000000000003 ZT12-15 2.45 2.45 2.45 ZT16-19 19.7 19.7 19.7 ZT20-23 33.35 33.35 33.35