condition mean min max ZT0-3 38.8 38.8 38.8 ZT4-7 8.8 8.8 8.8 ZT8-11 5.9 5.9 5.9 ZT12-15 6.4 6.4 6.4 ZT16-19 12.9 12.9 12.9 ZT20-23 25.45 25.45 25.45