condition mean min max ZT0-3 8.45319669625 7.875526766499999 9.030866626 ZT4-7 8.665609254 6.5840179765 10.747200531499999 ZT8-11 16.668159 14.06407045 19.27224755 ZT12-15 18.49881371 17.28892036 19.708707060000002 ZT16-19 16.197959982500002 15.77465154 16.621268425 ZT20-23 22.259935825 20.907240514999998 23.612631135