condition mean min max ZT0-3 10.75 10.75 10.75 ZT4-7 1.2 1.2 1.2 ZT8-11 2.4 2.4 2.4 ZT12-15 7.75 7.75 7.75 ZT16-19 5.8 5.8 5.8 ZT20-23 2.05 2.05 2.05