condition mean min max ZT0-3 3.6898866666666668 3.6898866666666668 3.6898866666666668 ZT4-7 2.0215699999999996 2.0215699999999996 2.0215699999999996 ZT8-11 9.888655 9.888655 9.888655 ZT12-15 52.533500000000004 52.533500000000004 52.533500000000004 ZT16-19 56.624 56.624 56.624 ZT20-23 12.4091 12.4091 12.4091