condition mean min max ZT0-3 16.784958555 16.55955788 17.01035923 ZT4-7 16.825236017500004 16.584354920000003 17.066117115 ZT8-11 15.664960814999999 15.283751774999999 16.046169855 ZT12-15 18.14684563 17.58366565 18.710025610000002 ZT16-19 16.970708657499998 15.63030222 18.311115094999998 ZT20-23 18.787308185 18.474813935 19.099802435