condition mean min max ZT0-3 12.4 12.4 12.4 ZT4-7 26.7 26.7 26.7 ZT8-11 13.8 13.8 13.8 ZT12-15 50.05 50.05 50.05 ZT16-19 24.85 24.85 24.85 ZT20-23 8.55 8.55 8.55