condition mean min max ZT0-3 11.964403 11.964403 11.964403 ZT4-7 9.973914 9.973914 9.973914 ZT8-11 9.545763 9.545763 9.545763 ZT12-15 11.6770955 11.6770955 11.6770955 ZT16-19 14.077999000000002 14.077999000000002 14.077999000000002 ZT20-23 10.242841 10.242841 10.242841