condition mean min max ZT0-3 31.098628 31.098628 31.098628 ZT4-7 34.641867 34.641867 34.641867 ZT8-11 37.24542099999999 37.24542099999999 37.24542099999999 ZT12-15 29.5865765 29.5865765 29.5865765 ZT16-19 27.088192999999997 27.088192999999997 27.088192999999997 ZT20-23 29.130148499999997 29.130148499999997 29.130148499999997