condition mean min max ZT0-3 15.3 15.3 15.3 ZT4-7 44.6 44.6 44.6 ZT8-11 33.5 33.5 33.5 ZT12-15 25.95 25.95 25.95 ZT16-19 21.3 21.3 21.3 ZT20-23 31.45 31.45 31.45