condition mean min max ZT0-3 14.2 14.2 14.2 ZT4-7 14.8 14.8 14.8 ZT8-11 17.6 17.6 17.6 ZT12-15 9.9 9.9 9.9 ZT16-19 39.85 39.85 39.85 ZT20-23 21.75 21.75 21.75