Year	per 1,000
1990	3.097674645892518
1991	3.0275307403043175
1992	2.9097382283195405
1993	2.818148554214723
1994	2.7272615782064356
1995	2.6909500188818836
1996	2.591740991209868
1997	2.4851637953057084
1998	2.386462254537163
1999	2.3477530010534604
2000	2.257946694966163
2001	2.1610110918594945
2002	2.1477213862618423
2003	2.0752527878832456
2004	2.3627819564621975
2005	1.999586017627743
2006	1.9398114884141475
2007	1.9273764382644853
2008	2.398324418606072
2009	1.8172821845557536
2010	1.749053935383129
2011	1.7240045103218133
2012	1.7136448239313518
2013	1.6430221326543781
2014	1.6014661580999452
2015	1.5798439870926373
2016	1.5705810638364994
2017	1.4847732064415258
2018	1.476308220340872
2019	1.4460836724018766
2020	1.4311190398391689
2021	1.3450828981990393
2022	1.3356572768899098