condition mean min max ZT0-3 7.1 7.1 7.1 ZT4-7 10.5 10.5 10.5 ZT8-11 8.35 8.35 8.35 ZT12-15 8.25 8.25 8.25 ZT16-19 14.45 14.45 14.45 ZT20-23 11.05 11.05 11.05