Year	per 1,000
1990	9.217274127227514
1991	8.531295077013361
1992	8.239383734663614
1993	8.0762687875603
1994	8.019048057977557
1995	7.850711382944053
1996	7.753015926632053
1997	7.637971673127617
1998	7.536929767226924
1999	7.429871696593098
2000	7.359697267373234
2001	7.308018974859667
2002	7.246893211474947
2003	7.181011387408013
2004	7.094858012944048
2005	6.957678732203374
2006	6.847181645636411
2007	6.647456468726186
2008	6.790091506253433
2009	6.3930021619314505
2010	6.308194272686433
2011	6.564336908619609
2012	7.749762810518163
2013	7.768945248727652
2014	7.415594956296554
2015	7.862175013381419
2016	7.531980220421018
2017	7.628669538674156
2018	7.960898221232745
2019	7.297144766324774
2020	6.889153980547932
2021	6.796763223367539
2022	6.698224451449161