Year per 1,000 1990 15.561542879987893 1991 15.765652690321255 1992 15.144264696547092 1993 15.320680530908392 1994 19.742779815961637 1995 14.715607524015443 1996 14.546813071667827 1997 13.95688928883406 1998 13.45537004682587 1999 12.976671718635021 2000 12.334376337231923 2001 11.939992748032468 2002 11.626786919499255 2003 11.35427695951323 2004 11.204485347893275 2005 10.848751005777247 2006 10.609986543559884 2007 10.365439648571307 2008 10.548655191781661 2009 9.935202412512202 2010 10.081650099293988 2011 9.641206970814657 2012 9.741936417877916 2013 9.707209937150122 2014 9.653239489061837 2015 9.711609377343432 2016 9.499051093654442 2017 9.362618263817957 2018 9.181754101079056 2019 8.777375858970437 2020 8.455126946019607 2021 8.215670748571355 2022 7.994546237535551