condition mean min max ZT0-3 15.85 15.85 15.85 ZT4-7 33.5 33.5 33.5 ZT8-11 15.45 15.45 15.45 ZT12-15 20.65 20.65 20.65 ZT16-19 24.55 24.55 24.55 ZT20-23 15.25 15.25 15.25