condition mean min max ZT0-3 4.05 4.05 4.05 ZT4-7 12.2 12.2 12.2 ZT8-11 10.9 10.9 10.9 ZT12-15 3.3 3.3 3.3 ZT16-19 7.8 7.8 7.8 ZT20-23 2.7 2.7 2.7