condition mean min max ZT0-3 30.97005 30.97005 30.97005 ZT4-7 25.6178 25.6178 25.6178 ZT8-11 20.38095 20.38095 20.38095 ZT12-15 17.583 17.583 17.583 ZT16-19 24.381999999999998 24.381999999999998 24.381999999999998 ZT20-23 26.7911 26.7911 26.7911