condition mean min max ZT0-3 0.8402810000000001 0.2991115 1.1923650000000001 ZT4-7 0.3920915 0.3920915 0.3920915 ZT8-11 0.16992400000000002 0.16992400000000002 0.16992400000000002 ZT12-15 0.6418010000000001 0.607121 0.676481 ZT16-19 0.7518825 0.7518825 0.7518825 ZT20-23 0.8886455 0.8886455 0.8886455