condition mean min max ZT0-3 5.0 5.0 5.0 ZT4-7 13.8 13.8 13.8 ZT8-11 28.4 28.4 28.4 ZT12-15 19.7 19.7 19.7 ZT16-19 8.7 8.7 8.7 ZT20-23 12.95 12.95 12.95