condition mean min max ZT0-3 17.27317649 14.8588108 19.68754218 ZT4-7 34.0748466525 30.281687420000004 37.868005885 ZT8-11 64.90959040000001 47.89008778 81.92909302000001 ZT12-15 56.6490123475 34.142149204999996 79.15587549 ZT16-19 28.339296672499998 22.860020805 33.81857254 ZT20-23 16.966432515 15.103987924999998 18.828877105000004