condition mean min max ZT0-3 26.411505 26.411505 26.411505 ZT4-7 28.155078500000002 28.155078500000002 28.155078500000002 ZT8-11 19.8479645 19.8479645 19.8479645 ZT12-15 59.9792525 59.9792525 59.9792525 ZT16-19 29.362394 29.362394 29.362394 ZT20-23 99.831428 99.831428 99.831428