condition mean min max ZT0-3 683.571837 683.571837 683.571837 ZT4-7 602.7947915 602.7947915 602.7947915 ZT8-11 736.114716 736.114716 736.114716 ZT12-15 761.9490605 761.9490605 761.9490605 ZT16-19 994.405021 994.405021 994.405021 ZT20-23 990.58043 990.58043 990.58043