Year	per 1,000
1990	18.757965737027487
1991	18.433486816947816
1992	17.98204917503183
1993	17.967980078022908
1994	22.04414319185723
1995	17.265074173073117
1996	17.158845671180906
1997	16.645012002267062
1998	16.39281056051551
1999	16.28428024893468
2000	15.565861987833342
2001	15.077697359464583
2002	14.61465460550531
2003	14.086297659489865
2004	13.714045694390032
2005	13.342747267677161
2006	12.705819745654809
2007	12.306082784688092
2008	12.271634698611019
2009	11.692142783429079
2010	11.689695070327442
2011	11.29477951646042
2012	11.398006657516866
2013	11.173237890370803
2014	10.911491755761642
2015	10.873870034700902
2016	10.588925443307282
2017	10.454135353113955
2018	10.412006462099617
2019	10.178242574619714
2020	10.040279802660143
2021	9.992887631633494
2022	9.9249853107177