condition mean min max ZT0-3 3.402625 3.355765 3.449485 ZT4-7 3.271605 3.271605 3.271605 ZT8-11 3.3607449999999996 3.3607449999999996 3.3607449999999996 ZT12-15 0 0 0 ZT16-19 3.5144 3.5144 3.5144 ZT20-23 3.663335 3.663335 3.663335