condition mean min max ZT0-3 20.7 20.7 20.7 ZT4-7 16.3 16.3 16.3 ZT8-11 30.4 30.4 30.4 ZT12-15 15.95 15.95 15.95 ZT16-19 4.85 4.85 4.85 ZT20-23 16.55 16.55 16.55