condition mean min max ZT0-3 3.2 3.2 3.2 ZT4-7 5.2 5.2 5.2 ZT8-11 11.55 11.55 11.55 ZT12-15 15.9 15.9 15.9 ZT16-19 3.35 3.35 3.35 ZT20-23 13.850000000000001 13.850000000000001 13.850000000000001