condition mean min max ZT0-3 1.32934684375 0.705711483 1.9529822045 ZT4-7 3.6069936257500004 1.8736180625 5.3403691890000005 ZT8-11 10.9732029865 8.689226536 13.257179437000001 ZT12-15 9.836494559 8.203879271 11.469109847 ZT16-19 6.21424400425 6.0574983625000005 6.370989646 ZT20-23 5.139990054 5.053104306 5.226875802