condition mean min max ZT0-3 13.2 13.2 13.2 ZT4-7 9.9 9.9 9.9 ZT8-11 8.95 8.95 8.95 ZT12-15 10.55 10.55 10.55 ZT16-19 12.0 12.0 12.0 ZT20-23 12.65 12.65 12.65