condition mean min max ZT0-3 14.9 14.9 14.9 ZT4-7 21.6 21.6 21.6 ZT8-11 21.6 21.6 21.6 ZT12-15 16.3 16.3 16.3 ZT16-19 12.65 12.65 12.65 ZT20-23 19.4 19.4 19.4