condition mean min max ZT0-3 7.35 7.35 7.35 ZT4-7 6.3 6.3 6.3 ZT8-11 19.8 19.8 19.8 ZT12-15 7.35 7.35 7.35 ZT16-19 8.0 8.0 8.0 ZT20-23 10.05 10.05 10.05