condition mean min max ZT0-3 2.9000000000000004 2.9000000000000004 2.9000000000000004 ZT4-7 3.1 3.1 3.1 ZT8-11 4.7 4.7 4.7 ZT12-15 2.35 2.35 2.35 ZT16-19 4.1 4.1 4.1 ZT20-23 4.1 4.1 4.1