condition mean min max ZT0-3 4.485469966 4.3336186230000004 4.637321309 ZT4-7 3.8570870599999996 3.4145196229999994 4.299654497 ZT8-11 3.7455224835000003 3.590954776 3.9000901910000003 ZT12-15 3.1181922650000002 2.4336297765 3.8027547535 ZT16-19 3.4194485937499994 2.7919466695 4.046950517999999 ZT20-23 5.032067859500001 4.8392453925000005 5.224890326500001