condition mean min max ZT0-3 14.428889 14.428889 14.428889 ZT4-7 37.918728 37.918728 37.918728 ZT8-11 59.4266595 59.4266595 59.4266595 ZT12-15 35.5771145 35.5771145 35.5771145 ZT16-19 23.016441999999998 23.016441999999998 23.016441999999998 ZT20-23 27.017277 27.017277 27.017277