condition mean min max ZT0-3 16.738833333333332 16.0592 17.826349999999998 ZT4-7 15.23535 15.23535 15.23535 ZT8-11 14.68955 14.68955 14.68955 ZT12-15 26.988625 26.1747 27.80255 ZT16-19 25.6438 25.6438 25.6438 ZT20-23 27.0909 27.0909 27.0909