condition mean min max ZT0-3 4.45 4.45 4.45 ZT4-7 2.2 2.2 2.2 ZT8-11 17.4 17.4 17.4 ZT12-15 1.7 1.7 1.7 ZT16-19 6.0 6.0 6.0 ZT20-23 4.15 4.15 4.15