condition mean min max ZT0-3 1.45 1.45 1.45 ZT4-7 1.0 1.0 1.0 ZT8-11 4.1 4.1 4.1 ZT12-15 4.65 4.65 4.65 ZT16-19 5.95 5.95 5.95 ZT20-23 15.6 15.6 15.6