Year	per 1,000
1990	3.9985037369158354
1991	3.929066706126893
1992	3.862957274949485
1993	3.8049530765633794
1994	3.712914049944787
1995	3.6342685757955073
1996	3.5516822596330746
1997	3.449401258065617
1998	3.367798959831878
1999	3.351586222379718
2000	3.186477333999658
2001	3.1099775932812035
2002	2.9846156525408083
2003	2.8870585021056345
2004	2.797933026038763
2005	2.7011736605218926
2006	2.6569717479133166
2007	2.5723471863013527
2008	2.548506929708207
2009	2.487978859334537
2010	2.4201477554424113
2011	2.3819728231466155
2012	2.2635316590336334
2013	2.1737141761026195
2014	2.153668240605952
2015	2.1273710489611033
2016	2.133289387592264
2017	2.144847972873876
2018	2.153452733747355
2019	2.1824566306243023
2020	2.245963738278358
2021	2.32756248600661
2022	2.4119093300807015