condition mean min max ZT0-3 21.25 21.25 21.25 ZT4-7 13.9 13.9 13.9 ZT8-11 14.05 14.05 14.05 ZT12-15 21.5 21.5 21.5 ZT16-19 26.95 26.95 26.95 ZT20-23 38.75 38.75 38.75