condition mean min max ZT0-3 4.7 4.7 4.7 ZT4-7 12.7 12.7 12.7 ZT8-11 11.75 11.75 11.75 ZT12-15 10.0 10.0 10.0 ZT16-19 3.45 3.45 3.45 ZT20-23 26.45 26.45 26.45