condition mean min max ZT0-3 21.25 21.25 21.25 ZT4-7 2.2 2.2 2.2 ZT8-11 12.75 12.75 12.75 ZT12-15 24.3 24.3 24.3 ZT16-19 8.0 8.0 8.0 ZT20-23 8.25 8.25 8.25