condition mean min max ZT0-3 24.110205 10.241415 34.8918 ZT4-7 7.431025 7.431025 7.431025 ZT8-11 9.82349 9.82349 9.82349 ZT12-15 14.967495 11.41404 18.52095 ZT16-19 20.262999999999998 20.262999999999998 20.262999999999998 ZT20-23 34.443 34.443 34.443