condition mean min max ZT0-3 2.9421125000000004 2.37678 3.507445 ZT4-7 3.9923200000000003 3.9923200000000003 3.9923200000000003 ZT8-11 2.381565 2.381565 2.381565 ZT12-15 0 0 0 ZT16-19 3.5030399999999995 3.5030399999999995 3.5030399999999995 ZT20-23 2.622865 2.622865 2.622865