condition mean min max ZT0-3 3.15 3.15 3.15 ZT4-7 9.3 9.3 9.3 ZT8-11 13.85 13.85 13.85 ZT12-15 2.9000000000000004 2.9000000000000004 2.9000000000000004 ZT16-19 10.1 10.1 10.1 ZT20-23 3.55 3.55 3.55