condition mean min max ZT0-3 9.85 9.85 9.85 ZT4-7 3.4 3.4 3.4 ZT8-11 6.95 6.95 6.95 ZT12-15 22.85 22.85 22.85 ZT16-19 5.3 5.3 5.3 ZT20-23 29.2 29.2 29.2