condition mean min max ZT0-3 17.9 17.9 17.9 ZT4-7 7.2 7.2 7.2 ZT8-11 45.4 45.4 45.4 ZT12-15 11.3 11.3 11.3 ZT16-19 17.5 17.5 17.5 ZT20-23 15.45 15.45 15.45