condition mean min max ZT0-3 5.4 5.4 5.4 ZT4-7 3.5 3.5 3.5 ZT8-11 4.45 4.45 4.45 ZT12-15 23.05 23.05 23.05 ZT16-19 4.0 4.0 4.0 ZT20-23 9.5 9.5 9.5