condition mean min max ZT0-3 4.4 4.4 4.4 ZT4-7 1.8 1.8 1.8 ZT8-11 2.7 2.7 2.7 ZT12-15 2.8 2.8 2.8 ZT16-19 10.45 10.45 10.45 ZT20-23 3.35 3.35 3.35