condition mean min max ZT0-3 444.194262 444.194262 444.194262 ZT4-7 820.1610525 820.1610525 820.1610525 ZT8-11 1044.2839435 1044.2839435 1044.2839435 ZT12-15 546.1261485 546.1261485 546.1261485 ZT16-19 913.4504955 913.4504955 913.4504955 ZT20-23 706.8923515 706.8923515 706.8923515