Year	per 1,000
1990	9.997276992325851
1991	9.818339052044985
1992	9.707130915742404
1993	9.732783710526842
1994	10.545771301222747
1995	9.661055249878684
1996	9.652567859634386
1997	9.56295668351789
1998	9.581536259569242
1999	9.615343324551278
2000	9.462707266065298
2001	9.34903696559899
2002	9.1462200755306
2003	8.967345923202442
2004	8.841128803315614
2005	8.575031749336423
2006	8.301944135887497
2007	8.100869844285116
2008	7.957757285396447
2009	7.664731561623718
2010	7.519096585470955
2011	7.302780313658042
2012	7.218589953417619
2013	7.092318845584717
2014	6.9630072522599376
2015	6.911913757398539
2016	6.7984185075912995
2017	6.717171531325889
2018	6.661054590013427
2019	6.539734214255679
2020	6.46398648016512
2021	6.433091151834478
2022	6.47480598864017