condition mean min max ZT0-3 23.999715 23.999715 23.999715 ZT4-7 22.363925000000002 22.363925000000002 22.363925000000002 ZT8-11 19.617863 19.617863 19.617863 ZT12-15 19.8095115 19.8095115 19.8095115 ZT16-19 21.375418 21.375418 21.375418 ZT20-23 20.634109000000002 20.634109000000002 20.634109000000002