condition mean min max ZT0-3 20.5 20.5 20.5 ZT4-7 10.5 10.5 10.5 ZT8-11 24.7 24.7 24.7 ZT12-15 18.0 18.0 18.0 ZT16-19 29.8 29.8 29.8 ZT20-23 32.95 32.95 32.95