condition mean min max ZT0-3 33.7 33.7 33.7 ZT4-7 3.4 3.4 3.4 ZT8-11 3.9 3.9 3.9 ZT12-15 10.1 10.1 10.1 ZT16-19 17.2 17.2 17.2 ZT20-23 19.2 19.2 19.2