condition mean min max ZT0-3 18.073875 14.0881 22.059649999999998 ZT4-7 10.62889 10.62889 10.62889 ZT8-11 9.614645 9.614645 9.614645 ZT12-15 0 0 0 ZT16-19 10.05009 10.05009 10.05009 ZT20-23 10.96405 10.96405 10.96405