condition mean min max ZT0-3 8.85 8.85 8.85 ZT4-7 24.7 24.7 24.7 ZT8-11 26.0 26.0 26.0 ZT12-15 21.8 21.8 21.8 ZT16-19 20.1 20.1 20.1 ZT20-23 21.0 21.0 21.0