condition mean min max ZT0-3 40.5 40.5 40.5 ZT4-7 42.4 42.4 42.4 ZT8-11 27.9 27.9 27.9 ZT12-15 8.7 8.7 8.7 ZT16-19 15.8 15.8 15.8 ZT20-23 54.35 54.35 54.35