condition mean min max ZT0-3 40.75 40.75 40.75 ZT4-7 33.4 33.4 33.4 ZT8-11 11.8 11.8 11.8 ZT12-15 22.0 22.0 22.0 ZT16-19 36.95 36.95 36.95 ZT20-23 35.25 35.25 35.25