condition mean min max ZT0-3 16.9 16.9 16.9 ZT4-7 8.6 8.6 8.6 ZT8-11 14.8 14.8 14.8 ZT12-15 11.85 11.85 11.85 ZT16-19 32.35 32.35 32.35 ZT20-23 26.4 26.4 26.4