Year per 1,000 1990 14.473943868166835 1991 14.511818166402533 1992 14.021141890171137 1993 14.029934442677455 1994 16.913810836101653 1995 13.431219038599444 1996 13.223089325589987 1997 12.724880175646673 1998 12.291139167160674 1999 11.85190843534044 2000 11.315282902697101 2001 10.95384436496709 2002 10.661196789809162 2003 10.414087844505977 2004 10.269641313320829 2005 10.219685809920104 2006 9.853348708116075 2007 9.687534189943916 2008 9.803963468834304 2009 9.373757504785074 2010 9.439265818251917 2011 9.093461120751055 2012 9.122804239053096 2013 9.062526742042508 2014 8.994004352587199 2015 9.00033033823274 2016 8.827897398949386 2017 8.688112453832272 2018 8.526427452429507 2019 8.204274213469395 2020 7.93518402008044 2021 7.718661700330604 2022 7.52238269597717