condition mean min max ZT0-3 9.6 9.6 9.6 ZT4-7 4.1 4.1 4.1 ZT8-11 28.4 28.4 28.4 ZT12-15 35.1 35.1 35.1 ZT16-19 15.15 15.15 15.15 ZT20-23 11.0 11.0 11.0