condition mean min max ZT0-3 1.3 1.3 1.3 ZT4-7 2.5 2.5 2.5 ZT8-11 1.3 1.3 1.3 ZT12-15 1.15 1.15 1.15 ZT16-19 2.4 2.4 2.4 ZT20-23 1.7 1.7 1.7