condition mean min max ZT0-3 6.45 6.45 6.45 ZT4-7 21.2 21.2 21.2 ZT8-11 19.2 19.2 19.2 ZT12-15 11.25 11.25 11.25 ZT16-19 3.8 3.8 3.8 ZT20-23 10.75 10.75 10.75