condition mean min max ZT0-3 2.4643800000000002 2.4643800000000002 2.4643800000000002 ZT4-7 2.05062 2.05062 2.05062 ZT8-11 3.0841849999999997 3.0841849999999997 3.0841849999999997 ZT12-15 3.816775 3.816775 3.816775 ZT16-19 4.5148 4.5148 4.5148 ZT20-23 3.0796833333333336 3.0796833333333336 3.0796833333333336