condition mean min max ZT0-3 19.05 19.05 19.05 ZT4-7 3.3 3.3 3.3 ZT8-11 9.0 9.0 9.0 ZT12-15 6.65 6.65 6.65 ZT16-19 31.1 31.1 31.1 ZT20-23 17.1 17.1 17.1