condition mean min max ZT0-3 8.0 8.0 8.0 ZT4-7 7.0 7.0 7.0 ZT8-11 3.0999999999999996 3.0999999999999996 3.0999999999999996 ZT12-15 3.4 3.4 3.4 ZT16-19 4.35 4.35 4.35 ZT20-23 5.9 5.9 5.9