condition mean min max ZT0-3 1.7561083333333334 1.32282 2.05069 ZT4-7 1.334085 1.334085 1.334085 ZT8-11 1.63646 1.63646 1.63646 ZT12-15 2.1854975 1.87181 2.4991849999999998 ZT16-19 2.769695 2.769695 2.769695 ZT20-23 2.66593 2.66593 2.66593