condition mean min max ZT0-3 3.82043 3.82043 3.82043 ZT4-7 2.862225 2.862225 2.862225 ZT8-11 1.929635 1.929635 1.929635 ZT12-15 1.9773 1.9773 1.9773 ZT16-19 2.94832 2.94832 2.94832 ZT20-23 3.749885 3.749885 3.749885