Year	per 1,000
1990	6.955085200452519
1991	7.082000528295325
1992	8.850942667347649
1993	9.10991821757663
1994	8.164149173854156
1995	7.585352541170874
1996	7.277083502622719
1997	7.001401797509956
1998	6.8454033398888035
1999	7.0506639591313585
2000	6.5370749969357655
2001	6.28026743543733
2002	5.989697895468773
2003	5.694711329816467
2004	5.485331826710949
2005	5.322203985000369
2006	5.197097970045901
2007	5.050088472378243
2008	4.8822558638288065
2009	4.52258030126124
2010	4.334447359961955
2011	4.101468332867695
2012	3.9289975147871785
2013	3.789217856638455
2014	3.7962814646634078
2015	3.5864867269591554
2016	3.627709604469368
2017	3.3389160390890833
2018	3.2068076449795218
2019	3.1509130495910753
2020	3.4157683019857887
2021	3.173826219346729
2022	4.305674531769854