condition mean min max ZT0-3 350.693115 350.693115 350.693115 ZT4-7 111.5716535 111.5716535 111.5716535 ZT8-11 178.4507605 178.4507605 178.4507605 ZT12-15 173.29787199999998 173.29787199999998 173.29787199999998 ZT16-19 417.7487005 417.7487005 417.7487005 ZT20-23 407.424082 407.424082 407.424082