condition mean min max ZT0-3 461.259365 461.259365 461.259365 ZT4-7 420.05144200000007 420.05144200000007 420.05144200000007 ZT8-11 440.9211545 440.9211545 440.9211545 ZT12-15 489.7706435 489.7706435 489.7706435 ZT16-19 441.58642799999996 441.58642799999996 441.58642799999996 ZT20-23 308.122083 308.122083 308.122083