condition mean min max ZT0-3 11.15 11.15 11.15 ZT4-7 7.2 7.2 7.2 ZT8-11 2.8 2.8 2.8 ZT12-15 11.75 11.75 11.75 ZT16-19 1.05 1.05 1.05 ZT20-23 17.5 17.5 17.5