condition mean min max ZT0-3 6.3 6.3 6.3 ZT4-7 23.4 23.4 23.4 ZT8-11 11.25 11.25 11.25 ZT12-15 25.8 25.8 25.8 ZT16-19 29.45 29.45 29.45 ZT20-23 15.8 15.8 15.8