condition mean min max ZT0-3 5.85 5.85 5.85 ZT4-7 2.2 2.2 2.2 ZT8-11 1.3 1.3 1.3 ZT12-15 2.05 2.05 2.05 ZT16-19 2.5999999999999996 2.5999999999999996 2.5999999999999996 ZT20-23 4.0 4.0 4.0