condition mean min max ZT0-3 12.0 12.0 12.0 ZT4-7 5.1 5.1 5.1 ZT8-11 10.45 10.45 10.45 ZT12-15 5.2 5.2 5.2 ZT16-19 7.35 7.35 7.35 ZT20-23 11.0 11.0 11.0