condition mean min max ZT0-3 2.75 2.75 2.75 ZT4-7 17.7 17.7 17.7 ZT8-11 4.2 4.2 4.2 ZT12-15 11.8 11.8 11.8 ZT16-19 0.85 0.85 0.85 ZT20-23 4.95 4.95 4.95