condition mean min max ZT0-3 5.5 5.5 5.5 ZT4-7 5.4 5.4 5.4 ZT8-11 5.6 5.6 5.6 ZT12-15 9.1 9.1 9.1 ZT16-19 9.9 9.9 9.9 ZT20-23 4.95 4.95 4.95