condition mean min max ZT0-3 1.1811783333333334 1.1811783333333334 1.1811783333333334 ZT4-7 1.651405 1.651405 1.651405 ZT8-11 0.7639685 0.7639685 0.7639685 ZT12-15 1.007326 1.007326 1.007326 ZT16-19 1.70231 1.70231 1.70231 ZT20-23 1.8478599999999998 1.8478599999999998 1.8478599999999998