Year	per 1,000
1990	3.102363047699494
1991	3.0353049897653412
1992	2.918761770175871
1993	2.826983916623504
1994	2.735967707424368
1995	2.7359549675821104
1996	2.6374527568187167
1997	2.530450424848056
1998	2.4322287057072685
1999	2.392145080277555
2000	2.302689328294632
2001	2.206076928525933
2002	2.1935329423920606
2003	2.0859325268379814
2004	2.3693036901968836
2005	2.0111288719234373
2006	1.9526384039496552
2007	1.9406112151119546
2008	2.403847914798971
2009	1.830876170347743
2010	1.7621979465947317
2011	1.7346595706677295
2012	1.7229907480009843
2013	1.6518572040006143
2014	1.6093808432754215
2015	1.5866065223363335
2016	1.5760426879816143
2017	1.4899066864248736
2018	1.4814029825255324
2019	1.4502203218419931
2020	1.4341636920337908
2021	1.3489911418357887
2022	1.3406483214775393