Year per 1,000 1990 5.552048511770351 1991 5.597069029535113 1992 6.281608934854697 1993 6.413648304136154 1994 5.900287864701033 1995 5.535681703969287 1996 5.227184117520889 1997 4.963502472603314 1998 4.794240430502227 1999 4.943780168630715 2000 4.432442518756223 2001 4.202567096223464 2002 3.9872274954777684 2003 3.773340930242207 2004 3.5757102651959185 2005 3.45508110633921 2006 3.3593040799292995 2007 3.2463165171770196 2008 3.1340111034726483 2009 3.0058126138591774 2010 2.9073241217033496 2011 2.8366655674122088 2012 2.7576771039769157 2013 2.7028555170686444 2014 2.7389560706552083 2015 2.685464359051626 2016 2.6708237643333534 2017 2.5513497551403073 2018 2.4901354696926474 2019 2.4420283942671035 2020 2.5306819336066138 2021 2.495599818823747 2022 3.067122688339308