condition mean min max ZT0-3 7.431743482 5.8650359089999995 8.998451055 ZT4-7 10.995468791250001 7.413193527500001 14.577744055 ZT8-11 23.3715835875 19.943106710000002 26.800060465 ZT12-15 32.200838489999995 27.485490995 36.916185985 ZT16-19 20.901790132499997 20.721034539999998 21.082545725 ZT20-23 21.2045315175 21.13801669 21.271046345000002