condition mean min max ZT0-3 17.5 17.5 17.5 ZT4-7 8.0 8.0 8.0 ZT8-11 14.45 14.45 14.45 ZT12-15 22.65 22.65 22.65 ZT16-19 14.5 14.5 14.5 ZT20-23 3.05 3.05 3.05