condition mean min max ZT0-3 1.6677866666666668 1.473815 1.8726800000000001 ZT4-7 3.6711549999999997 3.6711549999999997 3.6711549999999997 ZT8-11 5.88156 5.88156 5.88156 ZT12-15 5.567352499999999 5.449764999999999 5.684939999999999 ZT16-19 4.052770000000001 4.052770000000001 4.052770000000001 ZT20-23 3.20922 3.20922 3.20922