condition mean min max ZT0-3 19.1 19.1 19.1 ZT4-7 14.2 14.2 14.2 ZT8-11 22.0 22.0 22.0 ZT12-15 1.4 1.4 1.4 ZT16-19 15.75 15.75 15.75 ZT20-23 2.3 2.3 2.3