condition mean min max ZT0-3 14.0 14.0 14.0 ZT4-7 11.5 11.5 11.5 ZT8-11 4.5 4.5 4.5 ZT12-15 24.1 24.1 24.1 ZT16-19 2.6 2.6 2.6 ZT20-23 7.0 7.0 7.0