condition mean min max ZT0-3 12.48834806625 9.112149366 15.864546766499998 ZT4-7 21.273147332500002 19.60071459 22.945580075000002 ZT8-11 19.2490976325 18.834769235 19.66342603 ZT12-15 16.7177641225 16.257454795 17.17807345 ZT16-19 17.30666454 14.719678155 19.893650925 ZT20-23 30.5149920525 25.549428065 35.480556039999996