condition mean min max ZT0-3 416.934179 416.934179 416.934179 ZT4-7 640.839634 640.839634 640.839634 ZT8-11 425.5839775 425.5839775 425.5839775 ZT12-15 352.74536950000004 352.74536950000004 352.74536950000004 ZT16-19 220.34326600000003 220.34326600000003 220.34326600000003 ZT20-23 157.49849799999998 157.49849799999998 157.49849799999998