condition mean min max ZT0-3 3.9 3.9 3.9 ZT4-7 20.2 20.2 20.2 ZT8-11 20.95 20.95 20.95 ZT12-15 10.3 10.3 10.3 ZT16-19 8.75 8.75 8.75 ZT20-23 5.0 5.0 5.0