condition mean min max ZT0-3 13.45 13.45 13.45 ZT4-7 2.2 2.2 2.2 ZT8-11 12.75 12.75 12.75 ZT12-15 6.7 6.7 6.7 ZT16-19 13.35 13.35 13.35 ZT20-23 30.9 30.9 30.9