condition mean min max ZT0-3 16.15 16.15 16.15 ZT4-7 1.2 1.2 1.2 ZT8-11 2.7 2.7 2.7 ZT12-15 3.2 3.2 3.2 ZT16-19 11.7 11.7 11.7 ZT20-23 4.4 4.4 4.4