Year	per 1,000
1990	8.515594144767269
1991	8.411550120911373
1992	8.269545218765865
1993	8.272408734483731
1994	8.8902836086713
1995	8.044274057164403
1996	7.880226938505984
1997	7.651777384465726
1998	7.45958441120618
1999	7.319927142984449
2000	7.089173661314655
2001	6.9038424162755065
2002	6.758112606110265
2003	6.647652378868306
2004	6.543237308583306
2005	6.350251353782241
2006	6.170487723742918
2007	6.100528854153144
2008	6.10580609781836
2009	5.953660374088204
2010	5.972843792564756
2011	5.8392792195590415
2012	5.786938824148208
2013	5.722596051975615
2014	5.638819992739034
2015	5.5878839603866215
2016	5.465378013326204
2017	5.385052551109736
2018	5.24963446955632
2019	5.099298061000918
2020	4.94638541411012
2021	4.83270052208374
2022	4.769193899549772