condition mean min max ZT0-3 9.85 9.85 9.85 ZT4-7 1.6 1.6 1.6 ZT8-11 21.45 21.45 21.45 ZT12-15 5.65 5.65 5.65 ZT16-19 21.65 21.65 21.65 ZT20-23 16.3 16.3 16.3