condition mean min max ZT0-3 16.15 16.15 16.15 ZT4-7 6.2 6.2 6.2 ZT8-11 3.7 3.7 3.7 ZT12-15 4.85 4.85 4.85 ZT16-19 5.25 5.25 5.25 ZT20-23 1.7000000000000002 1.7000000000000002 1.7000000000000002